Výzkumná skupina instrumentální analýzy a bioanalýzy

@article{pmid35101791,

title = {Detection of pesticides in food products using paper-based devices by UV-induced fluorescence spectroscopy combined with molecularly imprinted polymers},

author = {Milada Vodova and Lukas Nejdl and Kristyna Pavelicova and Kristyna Zemankova and Tomas Rrypar and Dagmar Skopalova Sterbova and Jaroslava Bezdekova and Nantana Nuchtavorn and Mirek Macka and Vojtech Adam and Marketa Vaculovicova},

doi = {10.1016/j.foodchem.2022.132141},

issn = {1873-7072},

year  = {2022},

date = {2022-06-01},

journal = {Food Chem},

volume = {380},

pages = {132141},

abstract = {In this proof-of-concept study, we explore the detection of pesticides in food using a combined power of sensitive UV-induced fingerprint spectroscopy with selective capture by molecularly imprinted polymers (MIPs) and portable cost-effective paper-based analytical devices (PADs). The specific pesticides used herein as model compounds (both pure substances and their application products for spraying), were: strobilurins (i.e. trifloxystrobin), urea pesticides (rimsulfuron), pyrethroids (cypermethrine) and aryloxyphenoxyproponic acid herbicides (Haloxyfop-methyl). Commercially available spraying formulations containing the selected pesticides were positively identified by MIP-PADs swabs of sprayed apple and tomato. The key properties of MIP layer - imprinting factor (IF) and selectivity factor (α) were characterized using trifloxystrobin (IF-3.5, α-4.4) was demonstrated as a potential option for in-field application. The presented method may provide effective help with in-field testing of food and reveal problems such as false product labelling.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Mapping of melim melanoma combining icp-ms and maldi-msi methods.},

author = {VANÍČKOVÁ, L. and DO, T. and VEJVODOVÁ, M. and HORÁK, V. and HUBÁLEK, M. and EMRI, G. and ZEMÁNKOVÁ, K., and PAVELICOVÁ K. and KŘÍŽKOVÁ, S. and FALTUSOVÁ, V. and POMPEIANO, A. and VACULOVIČOVÁ, M. and ZÍTKA, O. and VACULOVIČ, T. and ADAM, V.},

url = {https://doi.org/10.1016/j.ijbiomac.2022.01.139},

year  = {2022},

date = {2022-05-11},

urldate = {2022-05-11},

journal = {International Journal of Biological Macromolecules},

volume = {vol. 203.},

pages = {583-592.},

abstract = {Here we developed a powerful tool for comprehensive data collection and mapping of molecular and elemental signatures in the Melanoma-bearing Libechov Minipig (MeLiM) model. The combination of different mass spectrometric methods allowed for detail investigation of specific melanoma markers and elements and their spatial distribution in tissue sections. MALDI-MSI combined with HPLC-MS/MS analyses resulted in identification of seven specific proteins, S100A12, CD163, MMP-2, galectin-1, tenascin, resistin and PCNA that were presented in the melanoma signatures. Furthermore, the ICP-MS method allowed for spatial detection of zinc, calcium, copper, and iron elements linked with the allocation of the specific binding proteins.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {The Conservation Status and Population Mapping of the Endangered Dracaena serrulata in the Dhofar Mountains, Oman},

author = {Vahalík, P.; and Patočka, Z.; and Drápela, K.; and Habrová, H.; and Ehrenbergerová, L.; and Lengálová, K.; and Kalivodová, H.; and Pompeiano Vaníčková, L.; and Al-Shamahi, E.; and Lupton, D.; and Al Issai, G.; and Al Hinai, A.; and Al Hatmi, S.; and Starnes, T.; and Maděra, P. },

url = {https://doi.org/10.3390/f11030322},

year  = {2022},

date = {2022-03-14},

journal = {Forests},

volume = {11},

issue = {3},

abstract = {Populations of Dracaena serrulata are disappearing at an alarming rate in the Arabian Peninsula. They are being destroyed by herders who use the leaves as fodder for camels, goats, and sheep during the dry season. Up until now, precise information about the current distribution and population status of D. serrulata in Oman have not been published. To fill this gap, the main aim of this work was to map the species distribution in the Dhofar Mountains (Oman) and to define the conservation and health status of the populations. Three isolated sub-populations of the study species were defined and mapped: the Jabal Samhan, Jabal al Qara, and Jabal al Qamar sub-populations. Dracaena serrulata occupies an area of 227 km2 in the Dhofar Mountains. More than 43,000 trees were counted, and 2387 trees were inventoried in total. The Jabal Samhan sub-population is an example of an extensively damaged population with 59% of the trees recorded as dead and only 21% healthy trees. Populationsin the western portions of the Dhofar Mountains., Jabal al Qamar, and Jabal al Qara are comparatively abundant stands of healthy trees with a higher proportion of seedlings. The health of trees is strongly influenced by accessibility and precipitation provided by the southwest summer monsoon: the healthy individuals predominate on the steep terrain along the seaward facing cliffs. },

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Distance-based detection in analytical flow devices: From gas detection tubes to microfluidic chips and microfluidic paper-based analytical devices},

author = {NUCHTAVORN, N. , and RYPAR, T., and NEJDL, L., and VACULOVICOVA, M., and MACKA, M.},

url = {https://doi.org/10.1016/j.trac.2022.116581},

issn = {0165-993},

year  = {2022},

date = {2022-03-01},

urldate = {2022-03-01},

journal = {TrAC – Trends in Analytical Chemistry},

volume = {150},

abstract = {Distance-based detection (DbD) in analytical flow devices was first described in the 1930s, based on a colorimetric measurement of gas samples passing through a tube with a solid porous packing showing a color change as it reacts with the gas, with the zone length proportional to the analyte concentration. Over the following decades, DbD was introduced to a variety of formats and platforms including capillary, microfluidic chips and microfluidic paper-based analytical devices. Most of the materials are easily functionalised, and disposable. The DbD principles are based on a visible color change resulting from various reactions ranging from simple colorimetric to specific ligand or antibody binding. The immense attractivity of DbD rests in its simplicity of quantitative readout without auxiliary instrumentation. This review outlines key historical developments during 1937–2021, detection principles, driving forces, instrumental formats, and application areas. Finally, ways to overcome limitations, improve the performance and future perspectives are discussed.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid34648791,

title = {Evaluation of mercury bioavailability and phytoaccumulation by means of a DGT technique and of submerged aquatic plants in an aquatic ecosystem situated in the vicinity of a cinnabar mine},

author = {Pavlína Pelcová and Radovan Kopp and Andrea Ridošková and Jan Grmela and Dagmar Štěrbová},

doi = {10.1016/j.chemosphere.2021.132545},

issn = {1879-1298},

year  = {2022},

date = {2022-02-01},

journal = {Chemosphere},

volume = {288},

number = {Pt 2},

pages = {132545},

abstract = {The ability of submerged aquatic plants (Elodea canadensis, Myriophyllum spicatum, Ceratophyllum demersum) and a natant plant (Eichhornia crassipes) to bioaccumulate mercury was evaluated in a laboratory experiment as well as in a real aquatic ecosystem situated in the vicinity of a cinnabar mine. Moreover, the ability of the diffusive gradients in the thin films technique (DGT) to predict mercury bioavailability for selected aquatic plants was tested. The submerged plants had sufficient bioaccumulation capacity for long-term phytoaccumulation of mercury in a real aquatic ecosystem. The determined bioaccumulation factor was greater than 1000. On average, the submerged plant leaves accumulated 13 times more mercury than the leaves of the natant aquatic plants. Chlorides at concentrations up to 200 mg/L had no statistically significant effect on mercury accumulation, nevertheless, the presence of humic acid in the water environment resulted in its significant (p < 0.002) decrease. A strong positive correlation (r > 0.66) was determined between mercury concentration in the input parts (leaves and/or roots) of the aquatic plants and the flow of mercury into DGT units.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Uv-light-actuated in-situ preparation of paper@zncd quantum dots for paper-based enzymatic nanoreactors.},

author = {KHUNKITCHAI, N. and NUCHTAVORN, N. and RYPAR, T. and VLCNOVSKA, M. and NEJDL, L. and VACULOVICOVA, M. and MACKA, M.},

url = {https://doi.org/10.1016/j.cej.2021.132508},

year  = {2022},

date = {2022-01-01},

urldate = {2022-01-01},

journal = {Chemical Engineering Journal.},

volume = {vol. 428.},

pages = {132508.},

abstract = {Quantum dots (QDs) have been widely applied in the analytical field including sensitive fluorescent assays on paper-based devices. A facile in-situ synthesis of QDs after a simple reagent deposition on paper could enable a rapid low-cost fabrication of QD–modified paper with a variety of properties and purposes such as enzymatic nanoreactors. Herein, for the first time, fluorescent ZnCd QDs were prepared by in-situ synthesis in the paper matrix using thiol-containing precursors and irradiation by UV light. A successful creation of the immobilized ZnCd QDs on paper (paper@ZnCd QDs) was monitored by their intrinsic fluorescence while their peroxidase mimetic activity was evaluated by a catalytic reaction between H2O2 and a substrate (3,3′,5,5′-tetramethylbenzidine, TMB) producing a blue coloured product of charged transfer complex of TMB (oxTMB). From three thiol precursors investigated, the insulin precursor provided a greater activity than glutathione (GSH) and both considerably larger than BSA. Finally, a QDs precursor mixture deposition onto the paper matrix was evaluated by the peroxidase-mimetic activity, which was comparable with a reference method. The in-situ preparation of paper@ZnCd QDs is simple, rapid and ‘green’, with potential in biomedical applications primarily as fluorescence imaging agent and enzyme mimetic paper-based nanoreactors.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid34496333,

title = {UV-Induced fingerprint spectroscopy},

author = {Lukas Nejdl and Martina Havlikova and Filip Mravec and Tomas Vaculovic and Veronika Faltusova and Kristyna Pavelicova and Mojmir Baron and Michal Kumsta and Vit Ondrousek and Vojtech Adam and Marketa Vaculovicova},

doi = {10.1016/j.foodchem.2021.130499},

issn = {1873-7072},

year  = {2022},

date = {2022-01-01},

journal = {Food Chem},

volume = {368},

pages = {130499},

abstract = {Here, we present the potential analytical applications of photochemistry in combination with fluorescence fingerprinting. Our approach analyzes the fluorescence of samples after ultraviolet light (UV) treatment. Especially in presence of metal ions and thiol-containing compounds, the fluorescence behavior changes considerably. The UV-induced reactions (changes) are unique to a given sample composition, resulting in distinct patterns or fingerprints (typically in the 230-600 nm spectral region). This method works without the need for additional chemicals or fluorescent probes, only suitable diluent must be used. The proposed method (UV fingerprinting) suggests the option of recognizing various types of pharmaceuticals, beverages (juices and wines), and other samples within only a few minutes. In some studied samples (e.g. pharmaceuticals), significant changes in fluorescence characteristics (mainly fluorescence intensity) were observed. We believe that the fingerprinting technique can provide an innovative solution for analytical detection.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {New insights into mechanisms of copper nanoparticle toxicity in freshwater algae Chlamydomonas reinhardtii: Effects on the pathways of secondary metabolites},

author = {Anna Janova and Martina Kolackova and Zuzana Bytesnikova and Petr Capal and Pavel Chaloupsky and Pavel Svec and Andrea Ridoskova and Natalia Cernei and Borivoj Klejdus and Lukas Richtera and Vojtech Adam and Dalibor Huska},

doi = {https://doi.org/10.1016/j.algal.2021.102476},

year  = {2021},

date = {2021-09-03},

urldate = {2021-09-03},

journal = {Algal Research},

volume = {60},

abstract = {The effects of copper nanoparticles (Cu-NPs), including their stability in the medium, were studied with the green unicellular algae Chlamydomonas reinhardtii (CC-125). Cu-NPs were synthesized and characterized. Cu-NP particles were uniform, regular, and largely spherical, and they had smooth surfaces; the average size was estimated to be 137.4 ± 2.1 nm. Chlamydomonas cells were cultivated for 96 h under controlled conditions in the presence of Cu-NPs, according to OECD guidelines, and then subjected to toxicological bioassays. Based on scanning electron microscopy (SEM) observations, the effects of Cu-NPs resulted in part from the dissolution of nanoparticles (NPs) and the action of copper itself, which shows the importance of studying NP stability in the testing environment. In this assay, deleterious effects were enhanced by increasing Cu-NP concentrations (5, 10, 25, 50, and 100 mg/L). Concentrations higher than 25 mg/L exhibited extreme toxicity. We confirmed the known toxic effects of metal NPs, namely, growth inhibition, reduction of chlorophyll levels in cells, cell penetration and increased ROS production. Attention was also paid to select underexplored metabolites, which were studied with a LC-MS/MS system. Treatments caused changes in metabolites profiles, and levels of p-hydroxybenzaldehyde and protocatechuic acid were especially enhanced, suggesting their positive roles in the antioxidant defence response. Furthermore, a repeatable increase in suberic acid levels was observed for various stress conditions tested, and we expect that this was the result of lipid peroxidation.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid33892369,

title = {Evaluation of mercury bioavailability to vegetables in the vicinity of cinnabar mine},

author = {Pavlína Pelcová and Andrea Ridošková and Jana Hrachovinová and Jan Grmela},

doi = {10.1016/j.envpol.2021.117092},

issn = {1873-6424},

year  = {2021},

date = {2021-08-01},

journal = {Environ Pollut},

volume = {283},

pages = {117092},

abstract = {Knowledge of the concentration of the bioavailable forms of mercury in the soil is necessary, especially, if these soils contain above-limit total mercury concentrations. The bioavailability of mercury in soil samples collected from the vicinity of abandoned cinnabar mines was evaluated using diffusive gradients in the thin films technique (DGT) and mercury phytoaccumulation by vegetables (lettuce, spinach, radish, beetroot, carrot, and green peas). Mercury was accumulated primarily in roots of vegetables. The phytoaccumulation of mercury into edible plant parts was site-specific as well as vegetable species-specific. The mercury concentration in edible parts decreased in the order: spinach leaf ≥ lettuce leaf ≥ carrot storage root ≥ beetroot storage root > radish storage root > pea legume. The translocation index as well as the target hazard quotient indicate the possible usability of soils from the vicinity of abandoned cinnabar mines for planting pod vegetables (peas). A strong positive correlation (r = 0.75 to 0.92, n > 30, p < 0.05) was observed between mercury concentration in secondary roots, the storage roots, leaves of vegetables and the flux of mercury from soil to the DGT units, and the effective concentration of mercury in soil solutions.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid33773713,

title = {Simultaneous determination of arsenic and uranium by the diffusive gradients in thin films technique using Lewatit FO 36: Optimization of elution protocol},

author = {Vendula Smolíková and Pavlína Pelcová and Andrea Ridošková and Martine Leermakers},

doi = {10.1016/j.talanta.2021.122234},

issn = {1873-3573},

year  = {2021},

date = {2021-06-01},

journal = {Talanta},

volume = {228},

pages = {122234},

abstract = {The sorption ability of Lewatit FO 36-DGT resin gel, which has been developed for arsenic determination, towards uranium was tested by batch experiments within this study for the first time. Since the uptake efficiency of uranium was 99.0 ± 0.4% and the maximum uptake capacity was not achieved even at the U spike of 1250 μg in the solution, the Lewatit FO 36 resin seems to be a suitable binding phase for DGT resin gels for the determination of uranium. The resin gel also does not display any significant sorption selectivity in favour of one element over another. A novel protocol for simultaneous elution of arsenic and uranium from Lewatit FO 36 resin gel was therefore proposed in this study. The elution efficiencies of 90.3 ± 3.9% and 85.2 ± 3.1% for As and U, respectively, were obtained using 5 mL of 1 M NaOH at 70 °C for 24 h. The comparison with the original elution protocol using microwave-assisted elution by 0.25 M NaOH and 0.17 M NaCl at 130 °C for 16 min indicates, that the novel elution protocol provides good results in the performance of arsenic elution and, in addition, allows simultaneous elution of uranium. Moreover, the elimination of NaCl from the elution process allows a fast and simple analysis of both elements using ICP-MS, and therefore, the Lewatit FO 36-DGT technique can become more commonplace among laboratories without the need to modify the analytical method as proposed in the original study.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid33714138,

title = {Potentials of Miscanthus x giganteus for phytostabilization of trace element-contaminated soils: Ex situ experiment},

author = {Florien Nsanganwimana and Karim Suhail Al Souki and Christophe Waterlot and Francis Douay and Aurélie Pelfrêne and Andrea Ridošková and Brice Louvel and Bertrand Pourrut},

doi = {10.1016/j.ecoenv.2021.112125},

issn = {1090-2414},

year  = {2021},

date = {2021-05-01},

journal = {Ecotoxicol Environ Saf},

volume = {214},

pages = {112125},

abstract = {Phytomanagement is proposed as a cost-effective and environmentally-friendly suggestion for sustainable use of large metal-contaminated areas. In the current work, the energy crop miscanthus (Miscanthus × giganteus) was grown in ex situ conditions on agricultural soils presenting a Cd, Pb and Zn contamination gradient. After 93 days of culture, shoot and root growth parameters were measured. Soils and plants were sampled as well to study the TE accumulation in miscanthus and the effects of this plant on TE mobility in soils. Results demonstrated that miscanthus growth depended more on the soils silt content rather than TE-contamination level. Moreover, soil organic carbon at T93 increased in the soils after miscanthus cultivation by 25.5-45.3%, whereas CaCl-extractible TEs decreased due to complex rhizosphere processes driving plant mineral uptake, and organic carbon inputs into the rhizosphere. In the contaminated soils, miscanthus accumulated Cd, Pb and Zn mainly in roots (BCF in roots: Cd " Zn > Pb), while strongly reducing the transfer of these elements from soil to all organs and from roots to rhizomes, stems and leaves (average TFs: 0.01-0.06, 0.11-1.15 and 0.09-0.79 corresponding to Cd, Pb and Zn respectively). Therefore, miscanthus could be considered a TE-excluder, hence a potential candidate crop for coupling phytostabilization and biomass production on the studied Metaleurop TE-contaminated soils.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Paperfluidic devices with a selective molecularly imprinted polymer surface for instrumentation-free distance-based detection of protein biomarkers.},

author = {Rypar, T., and Adam, V., and Vaculovicova, M. and & Macka, M. },

url = {https://doi.org/10.1016/j.snb.2021.129999},

year  = {2021},

date = {2021-04-19},

journal = {Sensors and Actuators B: Chemical},

volume = {341},

abstract = {Microfluidic paper-based analytical devices (μPADs) offer the advantages of simplicity, extremely low costs, robustness, and miniaturisation, synergistically supporting portability and point-of-care (POC) analysis. When μPADs are combined with distance-based detection in DμPADs, they uniquely enable a quantitative analytical platform that is truly instrumentation-free (naked-eye readout), or at least, does not require any specialised scientific instrumentation (only mobile phone camera). However, a significant drawback of DμPADs is their limited selectivity. In this work, we present for the first time molecularly imprinted polymer (MIP) as a selectivity-enhancing element in MIP-modified DμPADs (MIP-DμPADs). Herein, a layer of polydopamine MIP was coated onto the paper substrate of a DμPAD, in a simple process using dopamine as the monomer deposited onto the paper matrix in the migration-detection zone of the DμPAD, and polymerised in a rapid low cost procedure in the presence of oxygen under alkaline conditions. The polydopamine MIP-DμPAD was then systematically investigated for the selective determination of chymotrypsinogen (chymo) as a model protein biomarker in urine, within the linear concentration range 2.4–29.2 μM (R2 = 0,9903) with corresponding relative standard deviations ranging from 2% to 11 % and LOD =3.5 μM and LOQ =11.8 μM. The here presented analytical concept based on MIP-DμPADs has a potential in POC diagnostics, because of the combination of low cost automated fabrication, the rapid quantitative near to instrumentation-free analysis, and selectivity through the use of MIPs as a synthetic, more stable, cheaper and easily prepared alternative to bio-macromolecules.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid33946603,

title = {Tephritid Fruit Fly Semiochemicals: Current Knowledge and Future Perspectives},

author = {Francesca Scolari and Federica Valerio and Giovanni Benelli and Nikos T Papadopoulos and Lucie Vaníčková},

doi = {10.3390/insects12050408},

issn = {2075-4450},

year  = {2021},

date = {2021-04-01},

journal = {Insects},

volume = {12},

number = {5},

abstract = {The Dipteran family Tephritidae (true fruit flies) comprises more than 5000 species classified in 500 genera distributed worldwide. Tephritidae include devastating agricultural pests and highly invasive species whose spread is currently facilitated by globalization, international trade and human mobility. The ability to identify and exploit a wide range of host plants for oviposition, as well as effective and diversified reproductive strategies, are among the key features supporting tephritid biological success. Intraspecific communication involves the exchange of a complex set of sensory cues that are species- and sex-specific. Chemical signals, which are standing out in tephritid communication, comprise long-distance pheromones emitted by one or both sexes, cuticular hydrocarbons with limited volatility deposited on the surrounding substrate or on the insect body regulating medium- to short-distance communication, and host-marking compounds deposited on the fruit after oviposition. In this review, the current knowledge on tephritid chemical communication was analysed with a special emphasis on fruit fly pest species belonging to the  , and  genera. The multidisciplinary approaches adopted for characterising tephritid semiochemicals, and the real-world applications and challenges for Integrated Pest Management (IPM) and biological control strategies are critically discussed. Future perspectives for targeted research on fruit fly chemical communication are highlighted.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid33340626,

title = {Metallothionein dimerization evidenced by QD-based Förster resonance energy transfer and capillary electrophoresis},

author = {Kristyna Pavelicova and Lucie Vanickova and Yazan Haddad and Lukas Nejdl and Jan Zitka and Silvia Kociova and Filip Mravec and Tomas Vaculovic and Mirek Macka and Marketa Vaculovicova and Vojtech Adam},

doi = {10.1016/j.ijbiomac.2020.12.105},

issn = {1879-0003},

year  = {2021},

date = {2021-02-01},

journal = {Int J Biol Macromol},

volume = {170},

pages = {53--60},

abstract = {Herein, we report a new simple and easy-to-use approach for the characterization of protein oligomerization based on fluorescence resonance energy transfer (FRET) and capillary electrophoresis with LED-induced detection. The FRET pair consisted of quantum dots (QDs) used as an emission tunable donor (emission wavelength of 450 nm) and a cyanine dye (Cy3), providing optimal optical properties as an acceptor. Nonoxidative dimerization of mammalian metallothionein (MT) was investigated using the donor and acceptor covalently conjugated to MT. The main functions of MTs within an organism include the transport and storage of essential metal ions and detoxification of toxic ions. Upon storage under aerobic conditions, MTs form dimers (as well as higher oligomers), which may play an essential role as mediators in oxidoreduction signaling pathways. Due to metal bridging by Cd ions between molecules of metallothionein, the QDs and Cy3 were close enough, enabling a FRET signal. The FRET efficiency was calculated to be in the range of 11-77%. The formation of MT dimers in the presence of Cd ions was confirmed by MALDI-MS analyses. Finally, the process of oligomerization resulting in FRET was monitored by CE, and oligomerization of MT was confirmed.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Micellar electrokinetic chromatography as a powerful analytical tool for research on prebiotic chemistry.},

author = {ZEMANKOVA, K. and NEJDL, L. and BEZDEKOVA, J. and VODOVA, M. and PETERA, L. and PASTOREK, A. and CIVIS, S. and KUBELIK, P. and FERUS, M. and ADAM,V. and VACULOVICOVA, M.},

doi = {https://doi.org/10.1016/j.microc.2021.106022},

year  = {2021},

date = {2021-01-01},

urldate = {2021-01-01},

journal = {Microchemical Journal.},

volume = {167.},

pages = {7},

publisher = {ACS Appl. Mater. Interfaces},

abstract = {Capillary electromigration techniques have proven their capabilities in detection of variety of analytes from inorganic ions and small organic molecules through bio(macro)molecules to large analytes such as cells or nano/micro particles. Also broad range of potential applications includes food and environmental analysis, biomedical and pharmaceutical investigations or even diagnostics.



In this work, it was demonstrated that capillary micellar electrokinetic chromatography is an excellent tool extremely helpful in investigations focused on prebiotic synthesis of molecules essential for formation of life on early Earth – nucleobases. In particular, rapid separation of nucleobases (< 2 min) was achieved in 40 mM borate buffer separation electrolyte containing 60 mM sodium dodecyl sulfate as an additive. This approach enabled detection of nucleobases formed in thermolysed formamide under conditions simulating the environment occurring on early Earth. Moreover, polydopamine-based molecularly imprinted polymers specific to thymine and uracil improved detection of these low abundant products.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid34234435,

title = {The Anti-Proliferative Activity of Coordination Compound-Based ZnO Nanoparticles as a Promising Agent Against Triple Negative Breast Cancer Cells},

author = {Hana Stepankova and Marcin Swiatkowski and Rafal Kruszynski and Pavel Svec and Hana Michalkova and Vendula Smolikova and Andrea Ridoskova and Zbynek Splichal and Petr Michalek and Lukas Richtera and Pavel Kopel and Vojtech Adam and Zbynek Heger and Simona Rex},

doi = {10.2147/IJN.S304902},

issn = {1178-2013},

year  = {2021},

date = {2021-01-01},

journal = {Int J Nanomedicine},

volume = {16},

pages = {4431--4449},

abstract = {PURPOSE: The present study deals with the in vitro evaluation of the potential use of coordination compound-based zinc oxide (ZnO) nanoparticles (NPs) for the treatment of triple negative breast cancer cells (TNBrCa). As BrCa is one of the most prevalent cancer types and TNBrCa treatment is difficult due to poor prognosis and a high metastasis rate, finding a more reliable treatment option should be of the utmost interest.



METHODS: Prepared by reacting zinc carboxylates (formate, acetate, propionate, butyrate, isobutyrate, valerate) and hexamethylenetetramine, 4 distinct coordination compounds were further subjected to two modes of conversion into ZnO NPs - ultrasonication with oleic acid or heating of pure precursors in an air atmosphere. After detailed characterization, the resulting ZnO NPs were subjected to in vitro testing of cytotoxicity toward TNBrCa and normal breast epithelial cells. Further, their biocompatibility was evaluated.



RESULTS: The resulting ZnO NPs provide distinct morphological features, size, biocompatibility, and selective cytotoxicity toward TNBrCa cells. They internalize into two types of TNBrCa cells and imbalance their redox homeostasis, influencing their metabolism, morphology, and ultimately leading to their death via apoptosis or necrosis.



CONCLUSION: The crucial properties of ZnO NPs seem to be their morphology, size, and zinc content. The ZnO NPs with the most preferential values of all three properties show great promise for a future potential use in the therapy of TNBrCa.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid32797901,

title = {Continuous and real-time indoor and outdoor methane sensing with portable optical sensor using rapidly pulsed IR LEDs},

author = {Parvez Mahbub and Ansara Noori and John S Parry and John Davis and Arko Lucieer and Mirek Macka},

doi = {10.1016/j.talanta.2020.121144},

issn = {1873-3573},

year  = {2020},

date = {2020-10-01},

journal = {Talanta},

volume = {218},

pages = {121144},

abstract = {We designed a simple, portable, low-cost and low-weight nondispersive infrared (NDIR) spectroscopy-based system for continuous remote sensing of atmospheric methane (CH) with rapidly pulsed near-infrared light emitting diodes (NIR LED) at 1.65 μm. The use of a microcontroller with a field programmable gate array (μC-FPGA) enables on-the-fly and wireless streaming and processing of large data streams (~2 Gbit/s). The investigated NIR LED detection system offers favourable limits of detection (LOD) of 300 ppm (±5%) CH,. All the generated raw data were processed automatically on-the-fly in the μC-FPGA and transferred wirelessly via a network connection. The sensing device was deployed for the portable sensing of atmospheric CH at a local landfill, resulting in quantified concentrations within the sampling area (ca 400 m) in the range of 0.5%-3.35% CH. This NIR LED-based sensor system offers a simple low-cost solution for continuous real-time, quantitative, and direct measurement of CH concentrations in indoor and outdoor environments, yet with the flexibility provided by the custom programmable software. It possesses future potential for remote monitoring of gases directly from mobile platforms such as smartphones and unmanned aerial vehicles (UAV).},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid32507235,

title = {Radiometric characterisation of light sources used in analytical chemistry - A review},

author = {Parvez Mahbub and Mirek Macka},

doi = {10.1016/j.aca.2020.04.048},

issn = {1873-4324},

year  = {2020},

date = {2020-08-01},

journal = {Anal Chim Acta},

volume = {1123},

pages = {113--127},

abstract = {Light sources are an indispensable component of an overwhelmingly large number of analytical methods. Radiometric characterisation of light sources in analytical chemistry is therefore of fundamental importance. This review presents up to date knowledge on methods to characterise radiometric properties of light sources in terms of radiometric power, irradiance, brightness, luminous efficacy, luminous efficiency and emission spectra, all of which are crucial parameters for their use in analytical chemistry. Special attention is paid to radiometric characterisation of new generations of light sources with focus on miniaturised and low-cost light sources suitable for portable analytical instrumentation. Miniaturised light sources, especially new generations of solid-state light sources including solution processable quantum dot light emitting diodes (QLEDs), organic LEDs (OLEDs) as well as conventional LEDs and lasers, are radiometrically characterised through various spectrophotometric, actinometric as well as new facile radiometric methods. Although the areas of analytical use of new light sources including QLEDs, OLEDs as well as other important light sources such as deep ultraviolet (DUV) and infrared LEDs in analytical chemistry are yet to reach their potential, their radiometric characterisation opens future options for their wider deployment in analytical chemistry.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid32759824,

title = {UV-Induced Nanoparticles-Formation, Properties and Their Potential Role in Origin of Life},

author = {Lukas Nejdl and Kristyna Zemankova and Martina Havlikova and Michaela Buresova and David Hynek and Kledi Xhaxhiu and Filip Mravec and Martina Matouskova and Vojtech Adam and Martin Ferus and Jakub Kapus and Marketa Vaculovicova},

doi = {10.3390/nano10081529},

issn = {2079-4991},

year  = {2020},

date = {2020-08-01},

journal = {Nanomaterials (Basel)},

volume = {10},

number = {8},

abstract = {Inorganic nanoparticles might have played a vital role in the transition from inorganic chemistry to self-sustaining living systems. Such transition may have been triggered or controlled by processes requiring not only versatile catalysts but also suitable reaction surfaces. Here, experimental results showing that multicolor quantum dots might have been able to participate as catalysts in several specific and nonspecific reactions, relevant to the prebiotic chemistry are demonstrated. A very fast and easy UV-induced formation of ZnCd quantum dots (QDs) with a quantum yield of up to 47% was shown to occur 5 min after UV exposure of the solution containing Zn(II) and Cd(II) in the presence of a thiol capping agent. In addition to QDs formation, xanthine activity was observed in the solution. The role of solar radiation to induce ZnCd QDs formation was replicated during a stratospheric balloon flight.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid32278983,

title = {Magnetic molecularly imprinted polymers used for selective isolation and detection of Staphylococcus aureus},

author = {Jaroslava Bezdekova and Kristyna Zemankova and Jitka Hutarova and Silvia Kociova and Kristyna Smerkova and Vojtech Adam and Marketa Vaculovicova},

doi = {10.1016/j.foodchem.2020.126673},

issn = {1873-7072},

year  = {2020},

date = {2020-08-01},

journal = {Food Chem},

volume = {321},

pages = {126673},

abstract = {In this work, a novel method was developed, for isolation of S. aureus from complex (food) samples using molecular imprinting.  Dopamine was used as a functional monomer and fluorescence microscopy was used for detection. Conditions for preparation of molecularly imprinted polymers (MIPs), adsorption performance, adsorption kinetic, and selectivity of the polymeric layers were investigated. The various procedures were combined in a single extraction process, with the imprinted layer on the surface of the magnetic particles (magnetic MIPs). Subsequently, MIPs were used for extraction of S. aureus from milk and rice. Moreover, raw milk from cows with mastitis was tested successfully. Using this novel MIP-based method, it was possible to detect bacteria in milk at 1 × 10CFU·ml, which corresponds to the limit set in European Union legislation for microbial control of food.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid32307169,

title = {Molecularly imprinted polymers and capillary electrophoresis for sensing phytoestrogens in milk},

author = {Jaroslava Bezdekova and Marcela Vlcnovska and Kristyna Zemankova and Romana Bacova and Martina Kolackova and Tomas Lednicky and Jan Pribyl and Lukas Richtera and Lucie Vanickova and Vojtech Adam and Marketa Vaculovicova},

doi = {10.3168/jds.2019-17367},

issn = {1525-3198},

year  = {2020},

date = {2020-06-01},

journal = {J Dairy Sci},

volume = {103},

number = {6},

pages = {4941--4950},

abstract = {Dairy cow feed contains, among other ingredients, soybeans, legumes, and clover, plants that are rich in phytoestrogens. Several publications have reported a positive influence of phytoestrogens on human health; however, several unfavorable effects have also been reported. In this work, a simple, selective, and eco-friendly method of phytoestrogen isolation based on the technique of noncovalent molecular imprinting was developed. Genistein was used as a template, and dopamine was chosen as a functional monomer. A layer of molecularly imprinted polymers was created in a microtitration well plate. The binding capability and selective properties of obtained molecularly imprinted polymers were investigated. The imprinted polymers exhibited higher binding affinity toward chosen phytoestrogen than did the nonimprinted polymers. A selectivity factor of 6.94 was calculated, confirming satisfactory selectivity of the polymeric layer. The applicability of the proposed sensing method was tested by isolation of genistein from a real sample of bovine milk and combined with micellar electrokinetic capillary chromatography with UV-visible detection.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid32242258,

title = {Distance-based paper device using polydiacetylene liposome as a chromogenic substance for rapid and in-field analysis of quaternary ammonium compounds},

author = {Boonta Chutvirasakul and Nantana Nuchtavorn and Mirek Macka and Leena Suntornsuk},

doi = {10.1007/s00216-020-02583-y},

issn = {1618-2650},

year  = {2020},

date = {2020-05-01},

journal = {Anal Bioanal Chem},

volume = {412},

number = {13},

pages = {3221--3230},

abstract = {This work presents an affordable distance-based microfluidic paper-based device (μPAD), using polydiacetylene (PDA) liposome as a chromogenic substance with a smartphone-based photo editor, for rapid and in-field analysis of quaternary ammonium compounds (QACs) (e.g., didecyldimethylammonium chloride (DDAC), benzyldimethyltetradecyl ammonium chloride (BAC), and cetylpyridinium chloride (CPC)). In-field analysis of these compounds is important to ensure their antimicrobial activity and user safety since they are widely utilized as disinfectants in households and hospitals. The μPAD featured a thermometer-like shape consisting of a sample reservoir and a microchannel as the detection zone, which was pre-deposited with PDA liposome. The color change from blue to red appeared in the presence of QACs and the color bar lengths were proportional to the QAC concentrations. Reactions of QACs with the PDA required a specific pH range (from pH 4.0 to 10.0) and a readout time of 7 min. Analytical performance characteristics of the device were tested with DDAC, BAC, and CPC showing acceptable specificity, accuracy (96.1-109.4%), and precision (%RSDs ≤ 9.3%). Limits of detection and quantitation were in the ranges of 20 to 80 and 70 to 250 μM, respectively. Feasibility of the newly developed device was demonstrated for in-field analysis of QACs in fumigation solution providing comparable results with those obtained from a colorimetric assay (P > 0.05). The proposed device shows potentials for further applications of other analytes since it offers speed, simplicity, and affordability for in-field analysis, especially in remote areas where expertise, resources, and infrastructures are limited. Graphical abstract.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid32113552,

title = {Fully automated process for histamine detection based on magnetic separation and fluorescence detection},

author = {Milica Gagic and Lukas Nejdl and Kledi Xhaxhiu and Natalia Cernei and Ondrej Zitka and Ewelina Jamroz and Pavel Svec and Lukas Richtera and Pavel Kopel and Vedran Milosavljevic and Vojtech Adam},

doi = {10.1016/j.talanta.2020.120789},

issn = {1873-3573},

year  = {2020},

date = {2020-05-01},

journal = {Talanta},

volume = {212},

pages = {120789},

abstract = {To ensure food safety and to prevent unnecessary foodborne complications this study reports fast, fully automated process for histamine determination. This method is based on magnetic separation of histamine with magnetic particles and quantification by the fluorescence intensity change of MSA modified CdSe Quantum dots. Formation of FeO particles was followed by adsorption of TiO on their surface. Magnetism of developed probe enabled rapid histamine isolation prior to its fluorescence detection. Quantum dots (QDs) of approx. 3 nm were prepared via facile UV irradiation. The fluorescence intensity of CdSe QDs was enhanced upon mixing with magnetically separated histamine, in concentration-dependent manner, with a detection limit of 1.6 μM. The linear calibration curve ranged between 0.07 and 4.5 mM histamine with a low LOD and LOQ of 1.6 μM and 6 μM. The detection efficiency of the method was confirmed by ion exchange chromatography. Moreover, the specificity of the sensor was evaluated and no cross-reactivity from nontarget analytes was observed. This method was successfully applied for the direct analysis of histamine in white wine providing detection limit much lower than the histamine maximum levels established by EU regulation in food samples. The recovery rate was excellent, ranging from 84 to 100% with an RSD of less than 4.0%. The main advantage of the proposed method is full automation of the analytical procedure that reduces the time and cost of the analysis, solvent consumption and sample manipulation, enabling routine analysis of large numbers of samples for histamine and highly accurate and precise results.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid32290291,

title = {A Novel Ruthenium Based Coordination Compound Against Pathogenic Bacteria},

author = {Vishma Pratap Sur and Aninda Mazumdar and Pavel Kopel and Soumajit Mukherjee and Petr Vítek and Hana Michalkova and Markéta Vaculovičová and Amitava Moulick},

doi = {10.3390/ijms21072656},

issn = {1422-0067},

year  = {2020},

date = {2020-04-01},

journal = {Int J Mol Sci},

volume = {21},

number = {7},

abstract = {The current epidemic of antibiotic-resistant infections urges to develop alternatives to less-effective antibiotics. To assess anti-bacterial potential, a novel coordinate compound (RU-S4) was synthesized using ruthenium-Schiff base-benzimidazole ligand, where ruthenium chloride was used as the central atom. RU-S4 was characterized by scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), and Raman spectroscopy. Antibacterial effect of RU-S4 was studied against  (NCTC 8511), vancomycin-resistant  (VRSA) (CCM 1767), methicillin-resistant  (MRSA) (ST239: SCCmecIIIA), and hospital isolate . The antibacterial activity of RU-S4 was checked by growth curve analysis and the outcome was supported by optical microscopy imaging and fluorescence LIVE/DEAD cell imaging. In vivo (balb/c mice) infection model prepared with VRSA (CCM 1767) and treated with RU-S4. In our experimental conditions, all infected mice were cured. The interaction of coordination compound with bacterial cells were further confirmed by cryo-scanning electron microscope (Cryo-SEM). RU-S4 was completely non-toxic against mammalian cells and in mice and subsequently treated with synthesized RU-S4.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Metrics of growth habit derived from the 3D tree point cloud used for species determination-A new approach in botanical taxonomy tested on Dragon tree group example},

author = {Vahalík, P.; and Drápela, K.; and Procházková, A.; and Patočka, Z.; and Balková, M.; and Šenfeldr, M.; and Lengálová, K.; and Kalivodová, H.; and Vaníčková, L.; and Ehrenbergerová, L.; and Lvončík, S.; and Maděra, P.},

doi = {https://doi.org/10.3390/f11030272},

year  = {2020},

date = {2020-03-28},

journal = {Forests},

volume = {11},

issue = {3},

abstract = {Detailed, three-dimensional modeling of trees is a new approach in botanical taxonomy. Representations of individual trees are a prerequisite for accurate assessments of tree growth and morphological metronomy. This study tests the abilities of 3D modeling of trees to determine the various metrics of growth habit and compare morphological differences. The study included four species of the genus Dracaena: D. draco, D. cinnabari, D. ombet, and D. serrulata. Forty-nine 3D tree point clouds were created, and their morphological metrics were derived and compared. Our results indicate the possible application of 3D tree point clouds to dendrological taxonomy. Basic metrics of growth habit and coefficients derived from the 3D point clouds developed in the present study enable the statistical evaluation of differences among dragon tree species.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid32029112,

title = {Miniature and fully portable gradient capillary liquid chromatograph},

author = {Shing Chung Lam and Lewellwyn Joseph Coates and Mohamed Hemida and Vipul Gupta and Paul R Haddad and Mirek Macka and Brett Paull},

doi = {10.1016/j.aca.2019.12.014},

issn = {1873-4324},

year  = {2020},

date = {2020-03-01},

journal = {Anal Chim Acta},

volume = {1101},

pages = {199--210},

abstract = {A robust, portable and miniature battery powered gradient capillary liquid chromatograph (total weight ∼2.7 kg, without battery ∼2.0 kg), with integrated microfluidic injection, column heating and high sensitivity low-UV absorbance detection is presented. The portable capillary chromatograph, was applied with a packed reversed-phase capillary column (100 mm × 300 μm I.D., 5 μm ODS), housed within an integrated capillary column heater controlled by a proportional-integral-derivative (PID) chip module. The system delivered retention time and peak area relative standard deviation in isocratic mode of <0.7% (n = 10) and <3.3% (n = 10), respectively, and <0.1% (n = 10) and <2.3% (n = 10) respectively, for gradient elution mode. Detection was based upon a 255 nm light-emitting diode (LED) using one of two commercial capillary flow-cell options, namely a high sensitivity 12 nL Agilent capillary z-cell (HSDC) and a 45 nL Thermo Fisher Scientific UZ-View™ flow cell (UZFC). The HSDC, housed within a 3D printed detector arrangement, gave an effective pathlength of 1.01 mm (84% of nominal pathlength) and stray light of only 0.2%. Limits of detection for four test small molecule pharmaceuticals ranged from 65 to 101 μg L based upon a 316 nL injection volume, with separation efficiencies of between 18,000 and 29,700 N m, with sub-4 min run times. The portable capillary LC system was successfully coupled to a small footprint portable mass spectrometer (Microsaic 4500 MiD) to demonstrate compatibility and 'point-of-need' miniaturised LC-MS capability.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid32043994,

title = {Development and evaluation of the iron oxide-hydroxide based resin gel for the diffusive gradient in thin films technique},

author = {Vendula Smolíková and Pavlína Pelcová and Andrea Ridošková and Josef Hedbávný and Jan Grmela},

doi = {10.1016/j.aca.2019.12.042},

issn = {1873-4324},

year  = {2020},

date = {2020-03-01},

journal = {Anal Chim Acta},

volume = {1102},

pages = {36--45},

abstract = {An ion-exchange resin Lewatit FO 36 was used for the preparation of a new resin gel for the diffusive gradient in thin films technique (DGT). The DGT method was optimized for the accumulation of four bioavailable arsenic species (As, As, monomethylarsonic acid, dimethylarsinic acid) in the aquatic environment. The total sorption capacity of Lewatit FO 36 resin gel was 535 μg As disc. The microwave-assisted extraction in the presence of NaCl (10 g L) and NaOH (10 g L) was used for the isolation of arsenic species from the Lewatit FO 36 resin gel. The elution efficiency of arsenic was 98.4 ± 2.0%. Arsenic was determined by the optimized electrothermal atomic absorption spectrometry (ET-AAS) method using palladium modifier, pre-atomization cool-down step and tungsten carbides coating of graphite tube. The Lewatit FO 36 resin gel provides accurate results (c/c ratio 0.86-1.00) in the pH range 4-8. No significant influence of experimental conditions was observed in the presence of chlorides (0-0.5 mol L) and humic acid (0-100 mg L). Only a very high concentration of phosphates (10 mg L) caused a slight decrease in the diffusion coefficients of MMA and As species (8.4% and 12.4%, respectively). The presence of iron (0-1 mg L) caused a decrease in the diffusion coefficients, but with regard to the common concentrations of iron (less than 0.3 mg L), the negative effect was considered not significant for As and DMA in natural water. The DGT-ET-AAS method was applied for the determination of bioavailable arsenic species in the spiked river water samples and also in-situ in the water reservoir. The new resin gel was characterized by a homogeneous gel structure with excellent reproducibility (< 5% variation of results between batches) and high sorption capacity which suggests its possible long-term application (up to 286 days in the environment with the arsenic concentration of 100 μg L).},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {What We Know and What We Do Not Know about Dragon Trees?},

author = {Maděra, P.; and Forrest, A.; and Hanáček, P.; and Vahalík, P.; and Gebauer, R.; and Plichta, R.; and Jupa, R.; and Van Rensburg, J.J.; and Morris, M.; and Nadezhdina, N.; and Vaníčková, L.; and Jura-Morawiec, J.; and Wiland-Szymańska, J.; and Kalivodová, H.; and Lengálová, K.; and Rejžek, M.; and Habrová, H.},

url = {https://doi.org/10.3390/f11020236},

year  = {2020},

date = {2020-02-21},

urldate = {2020-02-21},

journal = {Forests},

volume = {11},

issue = {2},

abstract = {This article is a broad review focused on dragon trees—one of the most famous groups of trees in the world, well known from ancient times. These tertiary relicts are severely endangered in most of the area where they grow. The characteristic features of the dragon tree group are described and the species belonging to this group are listed. This review gathers together current knowledge regarding the taxonomy, evolution, anatomy and morphology, physiology, and ontogeny of arborescent dragon tree species. Attention is also paid to the composition, harvesting, medicinal, and ethnobotanical use of the resin (dragons’ blood). An evaluation of population structure, distribution, ecology, threats, and nature conservation forms the final part of the review. In the conclusions we recommend further avenues of research that will be needed to effectively protect all dragon tree species. },

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid31948590,

title = {Paper-based sol-gel thin films immobilized cytochrome P450 for enzyme activity measurement},

author = {Nantana Nuchtavorn and Jiraporn Leanpolchareanchai and Leena Suntornsuk and Mirek Macka},

doi = {10.1016/j.aca.2019.11.031},

issn = {1873-4324},

year  = {2020},

date = {2020-02-01},

journal = {Anal Chim Acta},

volume = {1098},

pages = {86--93},

abstract = {Cytochrome P450 (CYP450), and in particular CYP3A4, is the most abundantly expressed CYP450 isozyme implicated in many drug-drug and medicinal plant-drug interactions. Therefore, incorporation of CYP3A4 enzyme screening at an early stage of drug discovery is preferable in order to avoid enzymatic interactions. Here we present for the first time a paper-based CYP3A4 immobilized sol-gel-derived a platform using resorufin benzyl ether as a fluorogenic enzyme substrate used to investigate enzyme activity. The fluorescence intensity of the product can be simply quantified by using a handheld digital microscope and an image analysis software. The limit of quantitation was 0.35 μM with good precision (RSDs < 4.1%). Furthermore, the assay of CYP3A4 activity on the developed paper-based device provided comparable results with those obtained from conventional well-plates (p > 0.05), while offering simplicity and lower cost. Kinetic parameters of the immobilized CYP3A4 in sol-gel coated paper were calculated from the Lineweaver-Burk plot, including Michaelis constant (K) and maximum velocity (V), which were 2.71 ± 0.35 μM and 0.43 ± 0.05 μM/min, respectively. Moreover, a functional test of these devices was conducted by assessments of known CYP3A4 inhibitors (i.e. ketoconazole, itraconazole) and inducers (i.e. phenytoin, carbamazepine). To further demonstrate the broad range of uses, the devices were utilized to assay plant extracts i.e. Areca catechu seeds, Camellia sinensis leaves, Eclipta prostrata aerial part, providing results in good agreement with previous studies. Furthermore, the sol-gel immobilized enzyme stored at 4 °C can increase storage stability, offering the activity of 86.3 ± 0.4% after 3-weeks storage, equivalent to the activity of the free enzyme solution after 1-week storage. The developed paper-based devices offer versatility, portability and low-cost.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid31910952,

title = {One step multi-material 3D printing for the fabrication of a photometric detector flow cell},

author = {Farhan Cecil and Rosanne M Guijt and Alan D Henderson and Mirek Macka and Michael C Breadmore},

doi = {10.1016/j.aca.2019.10.075},

issn = {1873-4324},

year  = {2020},

date = {2020-02-01},

journal = {Anal Chim Acta},

volume = {1097},

pages = {127--134},

abstract = {Optical detection is the most common detection mode for many analytical assays. Photometric detection systems and their integration with analytical systems usually require several assembly parts and manual alignment of the capillary/tubing which affects sensitivity and repeatability. 3D printing is an innovative technology for the fabrication of integrated complex detection systems. One step multi-material 3D printing has been explored to fabricate a photometric detector flow cell from optically transparent and opaque materials using a dual-head FDM 3D printer. Integration of the microchannel, the detection window and the slit in a single device eliminates the need for manual alignment of fluidic and optical components, and hence improves sensitivity and repeatability. 3D printing allowed for rapid design optimisation by varying the slit dimension and optical pathlength. The optimised design was evaluated by determining stray light, effective path length and the signal to noise ratio using orange G. The optimised flow cell with extended path length of 10 mm and 500 μm slit yielded 0.02% stray light, 89% effective path length and detection limit of 2 nM. The sensitivity was also improved by 80% in the process of optimisation, using a blue 470 nm LED as a light source.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid31948590b,

title = {Paper-based sol-gel thin films immobilized cytochrome P450 for enzyme activity measurement},

author = {Nantana Nuchtavorn and Jiraporn Leanpolchareanchai and Leena Suntornsuk and Mirek Macka},

doi = {10.1016/j.aca.2019.11.031},

issn = {1873-4324},

year  = {2020},

date = {2020-02-01},

journal = {Anal Chim Acta},

volume = {1098},

pages = {86--93},

abstract = {Cytochrome P450 (CYP450), and in particular CYP3A4, is the most abundantly expressed CYP450 isozyme implicated in many drug-drug and medicinal plant-drug interactions. Therefore, incorporation of CYP3A4 enzyme screening at an early stage of drug discovery is preferable in order to avoid enzymatic interactions. Here we present for the first time a paper-based CYP3A4 immobilized sol-gel-derived a platform using resorufin benzyl ether as a fluorogenic enzyme substrate used to investigate enzyme activity. The fluorescence intensity of the product can be simply quantified by using a handheld digital microscope and an image analysis software. The limit of quantitation was 0.35 μM with good precision (RSDs < 4.1%). Furthermore, the assay of CYP3A4 activity on the developed paper-based device provided comparable results with those obtained from conventional well-plates (p > 0.05), while offering simplicity and lower cost. Kinetic parameters of the immobilized CYP3A4 in sol-gel coated paper were calculated from the Lineweaver-Burk plot, including Michaelis constant (K) and maximum velocity (V), which were 2.71 ± 0.35 μM and 0.43 ± 0.05 μM/min, respectively. Moreover, a functional test of these devices was conducted by assessments of known CYP3A4 inhibitors (i.e. ketoconazole, itraconazole) and inducers (i.e. phenytoin, carbamazepine). To further demonstrate the broad range of uses, the devices were utilized to assay plant extracts i.e. Areca catechu seeds, Camellia sinensis leaves, Eclipta prostrata aerial part, providing results in good agreement with previous studies. Furthermore, the sol-gel immobilized enzyme stored at 4 °C can increase storage stability, offering the activity of 86.3 ± 0.4% after 3-weeks storage, equivalent to the activity of the free enzyme solution after 1-week storage. The developed paper-based devices offer versatility, portability and low-cost.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid31759268,

title = {Terpenoid profiles of resin in the genus Dracaena are species specific},

author = {Lucie Vaníčková and Antonio Pompeiano and Petr Maděra and Tara Joy Massad and Petr Vahalík},

doi = {10.1016/j.phytochem.2019.112197},

issn = {1873-3700},

year  = {2020},

date = {2020-02-01},

journal = {Phytochemistry},

volume = {170},

pages = {112197},

abstract = {Dragon's blood is the colloquial name for the red resin produced by tree species in the genus Dracaena (Asparagaceae), and the resin is directly involved in plant defensive mechanisms against pathogen and herbivore attack. It is also widely used in traditional folk medicine due to its antiviral, antimicrobial and antitumor activities. In the present work, a method using solid phase microextraction combined with two-dimensional gas chromatography with time-of-flight mass spectrometric detection was developed for the analysis of resin from five Dracaena species, namely Dracaena cinnabari Balf. f., D. serrulata Baker, D. ombet Heuglin ex Kotschy & Peyr., D. draco subsp. draco, and D. draco subsp. ajgal. Twenty terpenoid components in the resins of the five species were identified after comparative study of the volatile metabolite profiles. Monoterpenes were found to be species specific, and the observed differences might be further investigated as a possible means of identifying chemotaxonomic markers. In addition, for the first time, we describe the terpenoid volatile profiles of D. ombet and D. serrulata resins.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid32867499,

title = {Miniaturized LC in Molecular Omics},

author = {Cemil Aydoğan and Francesca Rigano and Lenka Kujovská Krčmová and Doo Soo Chung and Mirek Macka and Luigi Mondello},

doi = {10.1021/acs.analchem.0c01436},

issn = {1520-6882},

year  = {2020},

date = {2020-01-01},

journal = {Anal Chem},

volume = {92},

number = {17},

pages = {11485--11497},

abstract = {Miniaturized LC has evolved at an exponential rate over the last 50 years. In the past decade, it has received considerable attention in the field of bioanalytical separation science and technology due to the need to measure different classes of biomolecules present in a variety of matrixes on a global scale to gain a deeper understanding of complex biological processes. This field has become a dominant area underpinning the molecular omics research (e.g., proteomics, metabolomics, lipidomics, and foodomics), allowing key insights into the function and mechanism of small to very large biomolecules on a molecular level. This Feature highlights the recent advances in molecular omics focusing on miniaturized LC technology combined with mass spectrometry-based platforms, with a particular emphasis on the strategies adopted and applications using new and sensitive nanoscale analytical methodologies.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid31706042,

title = {Application of molecularly imprinted polymers as artificial receptors for imaging},

author = {Tereza Vaneckova and Jaroslava Bezdekova and Gang Han and Vojtech Adam and Marketa Vaculovicova},

doi = {10.1016/j.actbio.2019.11.007},

issn = {1878-7568},

year  = {2020},

date = {2020-01-01},

journal = {Acta Biomater},

volume = {101},

pages = {444--458},

abstract = {Medical diagnostics aims at specific localization of molecular targets as well as detection of abnormalities associated with numerous diseases. Molecularly imprinted polymers (MIPs) represent an approach of creating a synthetic material exhibiting selective recognition properties toward the desired template. The fabricated target-specific MIPs are usually well reproducible, economically efficient, and stable under critical conditions as compared to routinely used biorecognition elements such as fluorescent proteins, antibodies, enzymes, or aptamers and can even be created to those targets for which no antibodies are available. In this review, we summarize the methods of polymer fabrication. Further, we provide key for selection of the core material with imaging function depending on the imaging modality used. Finally, MIP-based imaging applications are highlighted and presented in a comprehensive form from different aspects. STATEMENT OF SIGNIFICANCE: In this review, we summarize the methods of polymer fabrication. Key applications of Molecularly imprinted polymers (MIPs) in imaging are highlighted and discussed with regard to the selection of the core material for imaging as well as commonly used imaging targets. MIPs represent an approach of creating a synthetic material exhibiting selective recognition properties toward the desired template. The fabricated target-specific MIPs are usually well reproducible, economically efficient, and stable under critical conditions as compared to routinely used biorecognition elements, e.g., antibodies, fluorescent proteins, enzymes, or aptamers, and can even be created to those targets for which no antibodies are available.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid31996287,

title = {Direct Magnetic Bead-Based Extraction of MicroRNA from Urine with Capillary Electrophoretic Analysis Using Fluorescence Detection and Universal Label},

author = {Kristyna Smerkova and Tomas Rypar and Vojtech Adam and Marketa Vaculovicova},

doi = {10.1166/jbn.2020.2872},

issn = {1550-7033},

year  = {2020},

date = {2020-01-01},

journal = {J Biomed Nanotechnol},

volume = {16},

number = {1},

pages = {76--84},

abstract = {Short non-coding RNAs, specifically microRNAs (miRNAs), are of a great interest due to their presumed function in genome regulation. Moreover, miRNAs are currently perceived as potential biomarkers for numerous diseases; a variety of detection methods and sensing systems have therefore been studied. We present a magnetic-bead-based assay for specific miRNA isolation coupled with sensitive electrophoretic analysis with fluorescence detection. The magnetic separation step involves creating a duplex with targeted miR-141, which is subsequently cleaved from the magnetic bead surface with a specific endonuclease. The duplex is then determined using capillary electrophoresis with laser-induced fluorescence detection in the presence of the fluorescent dye PicoGreen for quantitating double-stranded DNA. The benefits of using microcolumn separation technique coupled with sensitive detection over traditionally used determination by fluorescence spectrometry include the fact that there is no need for a specific pre-labeled fluorescent probe. This significantly simplifies the method and reduces the costs. Cross-reactivity with mismatched oligonucleotides (3 and 5 mismatched bases) and different miRNAs (miR-124 and miR-150) was tested, demonstrating the specificity of the developed method for miRNA-141. This magnetic extraction method was demonstrated for the direct isolation and determination of miR-141 at different concentration levels from urine samples and the achieved nanomolar detection limit.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid32966310,

title = {Usability of graphene oxide as a mycotoxin binder: In vitro study},

author = {Pavel Horky and Eva Venusova and Tereza Aulichova and Andrea Ridoskova and Jiri Skladanka and Sylvie Skalickova},

doi = {10.1371/journal.pone.0239479},

issn = {1932-6203},

year  = {2020},

date = {2020-01-01},

journal = {PLoS One},

volume = {15},

number = {9},

pages = {e0239479},

abstract = {Mycotoxin management in agriculture is an essential challenge for maintaining the health of both animals and humans. Choosing the right adsorbent is still a question for many breeders and an important criterion for feed manufacturers. New adsorbents are still being sought. Graphene oxide is a promising material in the field of nanotechnology, which excels in its adsorption properties. Presented in vitro study investigates graphene oxide for the binding of mycotoxins from crushed wheat. The results show that graphene oxide has an adsorption capacity for aflatoxin 0.045 mg/g, zearalenone 0.53 mg/g and deoxynivalenol 1.69 mg/g at 37° C. In vitro simulation of crushed wheat digestion showed rapid adsorption during the gastric phase. Of the minerals, Mg, Cu and Zn were the most adsorbed. The applied dose of graphene oxide of 10 mg/g caused only a slight inhibition of the digestive enzymes α-amylase and trypsin compared to pepsin and gastric lipase. In vitro results indicated the suitability of graphene oxide in the adsorption of the aflatoxin, zearalenone and deoxynivalenol.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid32516439,

title = {Fractionation Analysis of Mercury in Soils: A Comparison of Three Techniques for Bioavailable Mercury Fraction Determination},

author = {Pavlína Pelcová and Andrea Ridošková and Jana Hrachovinová and Jan Grmela},

doi = {10.1002/etc.4797},

issn = {1552-8618},

year  = {2020},

date = {2020-01-01},

journal = {Environ Toxicol Chem},

volume = {39},

number = {9},

pages = {1670--1677},

abstract = {Knowledge of the fractionation of mercury in soils in the vicinity of abandoned cinnabar mines is essential for assessing the usability of soils for the cultivation of agriculturally important crops. Two different sequential extraction methods and the technique of diffusive gradients in thin films (DGT) were applied and compared for fractionation of mercury in soils from mercury-contaminated sites intended for farming purposes. The mercury found in these soils was primarily in the form of mercury sulfide (58.6-83.9%), followed by 6.7 to 15.4% of organically bound mercury and 2.9 to 23.2% of elemental mercury. Up to 10.3% of labile mercury species were determined by both sequential extraction methods in these soils. However, only 0.01 to 0.13% of mercury was determined as a bioavailable fraction using the DGT technique. Both sequential extraction methods tested for the fractionation analysis of mercury in contaminated soils were in excellent agreement. The content of the mobile (labile) mercury determined by the sequential extraction methods was statistically significantly higher (p < 0.0001) than the content of bioavailable mercury determined by the DGT technique. Environ Toxicol Chem 2020;39:1670-1677. © 2020 SETAC.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Surface-PASylation of ferritin to form stealth nanovehicles enhances in vivo therapeutic performance of encapsulated ellipticine},

author = {Barbora Tesarova, and Simona Dostalova, and Veronika Smidova, and Zita Goliasova, and Zuzana Skubalova, and Hana Michalkova, and David Hynek, and Petr Michalek, and Hana Polanska, and Marketa Vaculovicova, and Jaromir Hacek, and Tomas Eckschlager, and Marie Stiborova, and Ana S. Pires, and Ana R.M. Neves, and Ana M. Abrantes, and Tiago Rodrigues, and Paulo Matafome, and Maria F. Botelho, and Paulo Teixeira, and Fernando Mendes, and Zbynek Heger.},

url = {https://doi.org/10.1016/j.apmt.2019.100501},

year  = {2019},

date = {2019-12-04},

urldate = {2019-12-04},

journal = {Applied Materials Today},

volume = {18},

abstract = {Surface functionalisations substantially influence the performance of drug delivery vehicles by improving their biocompatibility, selectivity and circulation in bloodstream. Herein, we present the study of in vitro and in vivo behaviour of a highly potent cytostatic alkaloid ellipticine (Elli) encapsulated in internal cavity of ferritin (FRT)-based nanocarrier (hereinafter referred to as FRTElli). In addition, FRTElli surface was functionalised with three different molecular coatings: two types of protective PAS peptides (10- or 20-residues lengths) with sequences comprising amino acids proline (P), alanine (A) and serine (S) (to form PAS-10-FRTElli or PAS-20-FRTElli, respectively), or polyethylene glycol (PEG-FRTElli). All three surface modifications of FRT disposed sufficient encapsulation efficiency of Elli with no premature cumulative release of cargo. Noteworthy, all tested surface modifications displayed beneficial effects on the in vitro biocompatibility. PAS-10-FRTElli exhibited markedly reduced uptake by macrophages compared to PAS-20-FRTElli, PEG-FRTElli or unmodified FRTElli. The exceptional properties of PAS-10-FRTElli were validated by an array of in vitro analyses including formation of protein corona, uptake efficiency or screenings of selectivity of cytotoxicity. In murine preclinical model bearing triple-negative breast cancer (MDA-MB-231) xenograft, compared to free Elli or FRTElli, PAS-10-FRTElli displayed enhanced accumulation of Elli within tumour tissue, while hampering the uptake of Elli into off-target tissues. Noteworthy, PAS-10-FRTElli led to decreased in vivo complement (C3) activation and protein corona formation. Taken together, presented in vivo results indicate that PAS-10-FRTElli represents a promising stealth platform for translation into clinical settings.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid31228839,

title = {Evaluation of mercury availability to pea parts (Pisum sativum L.) in urban soils: Comparison between diffusive gradients in thin films technique and plant model},

author = {Pavlína Pelcová and Iveta Zouharová and Andrea Ridošková and Vendula Smolíková},

doi = {10.1016/j.chemosphere.2019.06.076},

issn = {1879-1298},

year  = {2019},

date = {2019-11-01},

journal = {Chemosphere},

volume = {234},

pages = {373--378},

abstract = {The diffusive gradients in thin films technique (DGT) was used for the determination of bioavailable mercury in urban soils, and results were compared to the mercury accumulation by Pisum sativum L. (pea) parts (leaf, root, stem, blossom, legume, and green seed). The total mercury concentration in soil samples was ranged between 0.084 and 0.326 mg kg. The soil solutions contained 0.15%-0.20% of mercury present in soils. In the soil solution, 2.21%-3.45% of mercury was available for DGT units. The highest mercury content was determined in the leaf and root of the pea plant, and the lowest in the consumable part of the pea plant (green seed). Mercury concentration in the parts of the pea plant increased over time, alongside the growth of the plant. The effect of acid precipitation on mercury bioavailability was statistically non-significant (p = 0.53). Significant and positive correlations were found between mercury flux into DGT unit, and mercury flux into the root (r = 0.989), leaf (r = 0.985), and stem (r = 0.904) of the pea plant. The obtained results suggest that the DGT method could be used for description of the uptake of mercury by pea plant parts in non-contaminated and slightly contaminated soils.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Fast pulsed amperometric waveform for miniaturised flow-through electrochemical detection: Application in monitoring graphene oxide reduction},

author = {Muhammed Ariful Islam and Aleksandra N. Koreshkova and Vipul Gupta, Trevor Lewis and Mirek Macka and Brett Paull and Parvez Mahbub

},

doi = {https://doi.org/10.1016/j.electacta.2019.135087},

issn = {0013-4686},

year  = {2019},

date = {2019-10-19},

journal = {Electrochimica Acta},

volume = {328},

abstract = {A fast pulsed waveform (2-steps at +400 mV and −400 mV, 10 ms each, 50 Hz cycle repetition) was developed incorporated within a miniaturised EC detector, and used to demonstrate the pulsed amperometric detection (PAD) of hydrazine in a flow-based analytical system. In contrast to standard amperometric detection (AD), a subsequent surface oxide reduction step was applied within the PAD waveform. The PAD applied within a simple flow-injection analysis (FIA) method provided a limit of detection (LOD) just as low as 0.8 nM of hydrazine (RSD 5%, n = 9, linearity r2 = 0.99 for 1 nM-100 μM), which is one order of magnitude lower than the lowest LOD reported todate. Significantly, the LOD was obtained using 5–20 times lower electrode surface area, flow rate, and sample volume, than in previous methods, with 15 times faster cycle repetition frequency than alternative PAD based studies reported in literature. Practical application of the PAD waveform was demonstrated by monitoring the temporal consumption of reducing agents during graphene oxide reduction experiments, separated using chromatographic methods (hydrazine in IC and ascorbic acid in HPLC).},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid31417990,

title = {Prebiotic synthesis at impact craters: the role of Fe-clays and iron meteorites},

author = {Adam Pastorek and Jana Hrnčířová and Luboš Jankovič and Lukáš Nejdl and Svatopluk Civiš and Ondřej Ivanek and Violetta Shestivska and Antonín KníŽek and Petr Kubelík and Jiří Šponer and Lukáš Petera and Anna Křivková and Giuseppe Cassone and Markéta Vaculovičová and Judit E Šponer and Martin Ferus},

doi = {10.1039/c9cc04627e},

issn = {1364-548X},

year  = {2019},

date = {2019-08-01},

journal = {Chem Commun (Camb)},

volume = {55},

number = {71},

pages = {10563--10566},

abstract = {Besides delivering plausible prebiotic feedstock molecules and high-energy initiators, extraterrestrial impacts could also affect the process of abiogenesis by altering the early Earth's geological environment in which primitive life was conceived. We show that iron-rich smectites formed by reprocessing of basalts due to the residual post-impact heat could catalyze the synthesis and accumulation of important prebiotic building blocks such as nucleobases, amino acids and urea.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Versatile persistent luminescent oxycarbonates: Morphology evolution from nanorods through bamboo-like nanorods to nanoparticles},

author = {Xiaojing Dou, Yang Li and Tereza Vaneckova and Ru Kang and Yihua Hu and Hongli Wen and Xiuping Gao and Shaoan Zhang and Marketa Vaculovicova and Gang Han

},

doi = {https://doi.org/10.1016/j.jlumin.2019.116635},

issn = {0022-2313},

year  = {2019},

date = {2019-07-20},

journal = {Journal of Luminescence},

volume = {215},

abstract = {Nanomaterials with persistent luminescence (PLNMs) have emerged as important materials in autofluorescence-free detection for their exceptional ability to temporarily detach the excitation and emission procedure. Although significant advances in materials composition have been made, research of morphology-dependent PLNMs synthesis is still lacking. At its core, further understanding toward the morphology optimization and afterglow enhancement is needed for their future expansion. Herein, we report a two-step synthesis to prepare morphology and afterglow controllable persistent luminescent oxycarbonates (La2O2CO3: Eu3+, Ho3+). In step one, we emphasized a precipitation pretreatment to ensure uniform precursor nanorods. Then, a morphology evolution from nanorods through bamboo-like nanorods to nanoparticles as well as the control of afterglow time can be realized by simply changing posttreatment conditions, such as reaction duration and reaction power. In particular, we highlighted the nanoparticles can be easily produced via cutting the bamboo-like nanorod section by section during the effortless mechanical grinding. In addition, the as-obtained PLNMs exhibit an excellent aqueous stability and remain suspended in adtevak from live mouse and 10% glucose beyond 10 days. The experiment of autofluorescence-free H2O2 detection with La2O2CO3: Eu3+, Ho3+ PLNMs employed as sensing probe demonstrates that these PLNMs present a fresh way of using PLNMs as a new H2O2 detection mode without in situ excitation for real time monitoring of H2O2 and glucose.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid30967173,

title = {Instrument-free argentometric determination of chloride via trapezoidal distance-based microfluidic paper devices},

author = {Mohammad Rahbar and Brett Paull and Mirek Macka},

doi = {10.1016/j.aca.2019.02.048},

issn = {1873-4324},

year  = {2019},

date = {2019-07-01},

journal = {Anal Chim Acta},

volume = {1063},

pages = {1--8},

abstract = {Chloride (Cl) is an inorganic anion present in a broad range of samples (e.g. biological, environmental, food, water, etc.), the determination of which is of widespread significance. In this work, we translate the well-established traditional argentometric method (Mohr's precipitation titration) into a small, simple, portable, and low-cost paper-based microfluidic diagnostic device, which provides rapid and quantitative analysis. The developed device enables the determination of chloride sample volumes as small as 5 μL. A distance-based detection method is implemented providing fully instrument-free quantitation. The beneficial effects of channel geometry (variable widths with constant heights) on analytical parameters were investigated. Trapezoidal channels (channel width changes linearly with height) were used to create a gradient of paper surface (titrant) available for the reaction, compared to the typical uniform rectangular channels (constant channel width). The trapezoid with increasing width offered higher sensitivity and lower detection limits (i.e. 0.05 mM vs 0.1 mM from the rectangular channel) for chloride determination across the concentration range of 0.05-25 mM. In addition, the effect of concentration of the deposited reagent on the obtained distance signals was investigated using varying concentrations of titrant (AgNO), which allowed determination of chloride across a wider dynamic range (up to 200 mM). The utility of the paper devices was demonstrated by determination of chloride in a variety of matrices including body fluids (sweat, serum, and urine) and water samples (drinking, mineral, river water).},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Electrochemical characterisation of nanoparticulate zirconium dioxide-on-gold electrode for electrochemical detection in flow-based analytical systems},

author = {Muhammed Ariful Islam and Mostafa A. Atia and Mirek Macka and Brett Paull and Parvez Mahbub

},

doi = {https://doi.org/10.1016/j.electacta.2019.06.031},

year  = {2019},

date = {2019-06-12},

journal = {Electrochimica Acta},

volume = {318},

pages = {61-68},

abstract = {The modification of gold (Au) electrode using zirconium dioxide nanoparticles (ZrO2 NPs) has been investigated for enhanced electrochemical (EC) detection in flow-based analytical systems. The average size of ZrO2 NPs deposited in a facile procedure on the Au electrode surface was calculated as 22.5 ± 7 nm. Redox behaviour of a test solute, ferrocyanide [Fe(CN)6]4-, on the bare- and ZrO2-Au electrodes was initially investigated using cyclic voltammetry. From the voltammograms of bare- and ZrO2-Au electrodes, the EC reversibility values and effective surface area were experimentally determined for the first-time in this study. Further, EC reversibility and 100% increase in effective electrode surface area were confirmed in ZrO2-Au electrode through investigating the detection response (current). The EC performance of the ZrO2-Au electrode was then investigated in amperometric detection of selected electroactive solutes separated by reversed-phase HPLC. The limits of detection (LODs), based upon an injection volume of 10 μL for ascorbic acid, 2,3-dihydroxybenzoic acid and pyrocatechol were 0.09 μM, 0.04 μM, and 0.10 μM, respectively (RSD 2.5%, n = 9, r2 = 0.99 for concentration range 1–100 μM). These LODs for the ZrO2-Au electrode were 2-times lower for 2,3-DHBA, and pyrocatechol than the lowest LODs reported in the literature for EC detection in HPLC. The ZrO2-Au electrode demonstrated satisfactory repeatability of preparation, detection reproducibility and high stability (8.5 h) during continuous-flow in FIA and 45 days during intermittent use with HPLC, at flow rate of 0.6 mL min−1. This work has demonstrated a comprehensive EC characterisation of Au electrode with nanoparticulate ZrO2 for flow-based analytical systems.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid30876553,

title = {Molecularly imprinted polymers coupled to mass spectrometric detection for metallothionein sensing},

author = {Tereza Vaneckova and Lucie Vanickova and Michaela Tvrdonova and Adam Pomorski and Artur Krężel and Tomas Vaculovic and Viktor Kanicky and Marketa Vaculovicova and Vojtech Adam},

doi = {10.1016/j.talanta.2019.01.089},

issn = {1873-3573},

year  = {2019},

date = {2019-06-01},

journal = {Talanta},

volume = {198},

pages = {224--229},

abstract = {We report a facile method for detection of metallothionein (MT), a promising clinically relevant biomarker, in spiked plasma samples. This method, for the first time, integrates molecularly imprinted polymers as purification/pretreatment step with matrix assisted laser desorption/ionization time-of-flight mass spectrometric detection and with laser ablation inductively coupled plasma mass spectrometry for analysis of MTs. The prepared MT-imprinted polydopamine layer showed high binding capacity and specific recognition properties toward the template. Optimal monomer (dopamine) concentration was found to be 16 mM of dopamine. This experimental setup allows to measure µM concentrations of MT that are present in blood as this can be used for clinical studies recognizing MT as marker of various diseases including tumour one. Presented approach not only provides fast sample throughput but also avoids the limitations of methods based on use of antibodies (e.g. high price, cross-reactivity, limited availability in some cases, etc.).},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Portable device for continuous sensing with rapidly pulsed LEDs – Part 1: Rapid on-the-fly processing of large data streams using an open source microcontroller with field programmable gate array},

author = {Ansara Noori and Parvez Mahbub and John S. Parry and John Davis and Arko Lucieer and Mirek Macka

},

doi = {https://doi.org/10.1016/j.measurement.2019.05.034},

issn = {0263-2241},

year  = {2019},

date = {2019-05-16},

urldate = {2019-05-16},

journal = {Measurement},

volume = {146},

pages = {749-757},

abstract = {We designed a portable system using an open source microcontroller (μC) with built-in field programmable gate array (FPGA) for on-the-fly data acquisition and processing of optical data generated from rapidly pulsed infrared light emitting diodes (IR LEDs) for optical sensing of gases. The system is used for rapid pulse generation (ca. 2 μs short pulses with a typical repetition rate of 1 kHz) to drive the IR LED, as well as for the optical sensing data acquisition and processing on-the-fly large data streams of ca. 2 Gbit/s. The flexibility and performance of the system is demonstrated. Each of the digitally processed signal pulses yielded one data point of analytical signal in time as a quasi-continuous data stream produced at a rate of between 1000 and 0.1 Hz. This microcontroller–based portable open source platform is then implemented in on-the-fly data acquisition and processing, of analytical signals enabling continuous gas sensing.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid30685027,

title = {Prospects of pulsed amperometric detection in flow-based analytical systems - A review},

author = {Muhammed Ariful Islam and Parvez Mahbub and Pavel N Nesterenko and Brett Paull and Mirek Macka},

doi = {10.1016/j.aca.2018.10.066},

issn = {1873-4324},

year  = {2019},

date = {2019-04-01},

journal = {Anal Chim Acta},

volume = {1052},

pages = {10--26},

abstract = {Electrochemical (EC) detection techniques in flow-based analytical systems such as flow injection analysis (FIA), capillary electrophoresis (CE), and liquid chromatography (LC) have attracted continuous interest over the last three decades, leading to significant advances in EC detection of a wide range of analytes in the liquid phase. In this context, the unique advantages of pulsed amperometric detection (PAD) in terms of high sensitivity and selectivity, and electrode cleaning through the application of pulsed potential for noble metal electrodes (e.g. Au, Pt), have established PAD as an important detection technique for a variety of electrochemically active compounds. PAD is especially valuable for analytes not detectable by ultraviolet (UV) photometric detection, such as organic aliphatic compounds and carbohydrates, especially when used with miniaturised capillary and chip-based separation methods. These applications have been accomplished through advances in PAD potential waveform design, as well as through the incorporation of nanomaterials (NMs) employed as microelectrodes in PAD. PAD allows on-line pulsed potential cleaning and coupling with capillary or standard separation techniques. The NMs are largely employed in microelectrodes to speed up mass and electron transfer between electrode surfaces and to perform as reactants in EC analysis. These advances in PAD have improved the sensitive and selective EC detection of analytes, especially in biological samples with complex sample matrices, and detection of electro-inactive compounds such as aliphatic organic compounds (i.e., formic acid, acetic acid, maleic acids, and β-cyclodextrin complexes). This review addresses the fundamentals of PAD, the role of pulsed sequences in AD, the utilisation of different EC detectors for PAD, technological advancements in PAD waveforms, utilisation of microelectrodes in PAD techniques, advances in the use of NMs in PAD, the applications of PAD, and prospects for EC detection, with emphasis on PAD in flow-based systems.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Trends in analytical separations of magnetic (nano)particles},

author = {Mónica N. Alves, and Manuel Miró, and Michael C. Breadmore, and Mirek Macka,

},

url = {https://doi.org/10.1016/j.trac.2019.02.026},

year  = {2019},

date = {2019-03-02},

urldate = {2019-03-02},

journal = {TrAC Trends in Analytical Chemistry},

volume = {114},

abstract = {Magnetic particles (MPs) and magnetic nanoparticles (MNPs) are appealing candidates for biomedical and analytical applications due to their unique physical and chemical properties. Given that magnetic fields can be readily used to control the motion and properties of M(N)Ps, their integration in analytical methods opens new avenues for sensing and quantitative analysis. There is a large body of literature related to their synthesis, with a relatively small number of methods reporting the analysis of M(N)Ps using separation methods, which provide information on their purity and monodispersity. This review discusses analytical separation methods of M(N)Ps published between 2013 and June 2018. The analytical separation methods evaluated in this work include (i) field flow fractionation, (ii) capillary electrophoresis, (iii) macroscale magnetophoresis and (iv) microchip magnetophoresis. Among the trends in analytical separations of M(N)Ps an inclination towards miniaturization is moving from conventional benchtop methods to rapid and low-cost methods based on microfluidic devices.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid30517841,

title = {Mass spectrometric imaging of cysteine rich proteins in human skin},

author = {Lucie Vanickova and Roman Guran and Sándor Kollár and Gabriella Emri and Sona Krizkova and Tomas Do and Zbynek Heger and Ondrej Zitka and Vojtech Adam},

doi = {10.1016/j.ijbiomac.2018.11.272},

issn = {1879-0003},

year  = {2019},

date = {2019-03-01},

journal = {Int J Biol Macromol},

volume = {125},

pages = {270--277},

abstract = {Looking insight pathological processes, metallothioneins (MTs) are considered to be potential biomarkers for monitoring of a development of various types of diseases, such as cancer. The early identification of the MTs in biological tissues could be important tool for the estimation of appropriate clinical therapy. Therefore, here we investigated the application of matrix assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) together with immunohistochemical analyses (IHC) using MT-1/2 antibody for MT detection in formalin-fixed paraffin-embedded (FFPE) biopsy specimens of human skin. Principal component analyses revealed differences in the peptide/protein profiles separating healthy skin from the carcinoma specimens. Statistically significant ion peaks at m/z 6038, 6300, 6676, and 7026 were more frequently detected in squamous cell carcinoma (SCC), basal cell carcinoma (BCC) and melanoma. Using IHC, we found that MT-1/2 was significantly higher in SCC and melanoma compared to healthy skin. Surprisingly, significantly low levels of MT-1/2 were found in BCC. On one side, the results indicate important role of MTs in melanoma occurrence and progression, as on the second side, there are hidden processes associated with MTs based on differences of the occurrence of the MS peaks, which could be associated with cycling of MTs isoforms.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Capillary gap flow cell as capillary-end electrochemical detector in flow-based analysis},

author = {Muhammed Ariful Islam and Shing Chung Lam and Yan Li and Mostafa A. Atia and Parvez Mahbub and Pavel N. Nesterenko and Brett Paull and Mirek Macka

},

doi = {https://doi.org/10.1016/j.electacta.2019.02.026},

year  = {2019},

date = {2019-02-12},

journal = {Electrochimica Acta},

volume = {303},

pages = {85-93},

abstract = {A gap flow cell (gap-FC) as a capillary-end electrochemical (EC) detector, incorporating exchangeable screen-printed electrodes, that facilitates adjustment of the gap distance between the capillary outlet and working electrode down to 30 μm was investigated. The analytical performance of the gap-FC was assessed in terms of detector response (current), the efficiency of EC conversion of ferrocyanide, and effective cell volume, as a function of flow rate and gap distance, within a range of 0.1–200 μL min−1 and 30–100 μm, respectively. As a result, an efficiency of EC conversion within the range of ∼1.5–11% (∼3–16 times higher than wall-jet FC), at an effective cell volume of ∼30–75 nL, was achieved. The gap-FC was applied as a liquid chromatography EC detector, coupled with standard and capillary format liquid chromatographs, where the analytical performance of gap-FC was compared with that of a UV detector. With the standard LC, the sensitivity for ascorbic acid, 2,3-dihydroxybenzoic acid and pyrocatechol, was greater than with the UV detector, with limits of detection (LODs) one order of magnitude lower for the gap-FC (0.10 μM, 0.09 μM, 0.19 μM, respectively, RSD 1.35–3.8%, n = 9, linearity r2 ∼0.99 for concentration range 1–100 μM). LODs of test electroactive solutes using the gap-FC were ∼2 times lower than LODs reported in existing literature using standard EC detectors, including wall-jet and thin-layer FCs.},

keywords = {},

pubstate = {published},

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