No (3370)
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Determination of Selected Drugs using 3D Printed Electrodes
Choińska-Mlynarczyk, Marta; Hrdlička, Vojtěch; Navrátil, Tomáš
2021 - English
The main aim of this research was to develop a new method for voltammetric determination of\npopular antidepressants, analgesics, and illicit drugs using a laboratory-made 3D printed\nelectrode and to compare the achieved results with those registered using a commercially\navailable glassy carbon electrode. These experiments represent the first step in the development\nof a method applicable in clinical and forensic praxis for the rapid and inexpensive\ndetermination of commonly misused groups of biologically active compounds.
Keywords:
analgesics; antidepressants; biologically active compounds
Available on request at various institutes of the ASCR
Determination of Selected Drugs using 3D Printed Electrodes
The main aim of this research was to develop a new method for voltammetric determination of\npopular antidepressants, analgesics, and illicit drugs using a laboratory-made 3D printed\nelectrode and to ...
Application potential of screening in vitro toxicological assays in qualitative risk assessment of nanomaterials
Závodná, Táňa; Topinka, Jan; Danihelka, J.
2020 - English
Undeniable benefits of engineered nanomaterials might be discredited by their potential enhanced or unexpected toxicity arising from nano-specific properties and behavior. An analysis of the applicability of the traditional chemical risk assessment approach in nanomaterials revealed high levels of uncertainty in both hazard characterization and exposure assessment due to the lack of relevant validated methods and reliable data. This indicates the limited capability of the conventional risk assessment approach to ensure the safe use of nanomaterials. Based on the identified uncertainties, the control banding approach was proposed as a suitable tool for preliminary qualitative risk assessment of nanomaterials in occupational settings. Control banding categorizes hazard and exposure into levels referred to as bands. The combination of the hazard and exposure bands results in a risk band determining the necessary degree of control and regulatory measures. To decrease the number of cases where, based on the precautionary principle, unavailable experimental or field data would lead to the assignment to the highest hazard category requiring costly exposure control, screening evaluation of nanomaterial toxicity was proposed as an additional decision criterion. For this purpose, a battery of in vitro toxicological assays enabling screening evaluation of potential toxic effects of NMs was proposed. The assays evaluate endpoints covering basic toxic effects of substances (cytotoxicity, genotoxicity), as well as known nonspecific mechanisms of toxicity typical for nanomaterials (oxidative stress, inflammation). The proposed risk management strategy is intended to assist small and medium-sized enterprises to implement adequate measures to ensure employee safety.
Keywords:
toxicity; tool; industrial poisons
Available at various institutes of the ASCR
Application potential of screening in vitro toxicological assays in qualitative risk assessment of nanomaterials
Undeniable benefits of engineered nanomaterials might be discredited by their potential enhanced or unexpected toxicity arising from nano-specific properties and behavior. An analysis of the ...
Copper complexes with triazoles
Jaklová Dytrtová, Jana; Jakl, M.
2020 - English
Triazoles are artificial chemicals used as fungicides as well as for pharmaceutical treatment. However, their reactivity is highly influenced by the presence of other chemicals. Especially, the presence of copper cations changes the reactivity of triazole by theoretically unexpected way. We have studied the interactions of the triazole ring with copper cations to help explain the reactivity of triazoles as a group.
Keywords:
triazoles; Cu(I); Cu(II); mass spectrometry; ESI-MS; complexes
Available at various institutes of the ASCR
Copper complexes with triazoles
Triazoles are artificial chemicals used as fungicides as well as for pharmaceutical treatment. However, their reactivity is highly influenced by the presence of other chemicals. Especially, the ...
Separation of triazoles from real samples with capillary electrophoresis
Kovač, Ishak; Jakl, M.; Šolínová, Veronika; Jaklová Dytrtová, Jana
2020 - English
The CE has become one of the advantageous tools in fungicides analysis in complex matrices due to its simplicity and separation efficiency. The separation of a group of thee triazole (i.e. penconazole, tebuconazole, and cyproconazole) fungicides was achieved with CD-MEKC with anionic Sg-CD as a selector at pH=4,8. The background electrolyte consisted of TRIS phosphate buffer (50 mmol/L) and 15 mmol/L SDS. The separation was performed on uncoated fused silica capillary with 500/425 mm (total/effective) length under -15 kV separation voltage. Achieved LOD values with this method were: 0,73, 1,88, 0,60, 1,18 (umol/L) for penconazole, tebuconazole, cyproconazole A and B respectively.
Keywords:
capillary electrophoresis; penconazole; tebuconazole; cyproconazole; γ-cyclodextrin
Available at various institutes of the ASCR
Separation of triazoles from real samples with capillary electrophoresis
The CE has become one of the advantageous tools in fungicides analysis in complex matrices due to its simplicity and separation efficiency. The separation of a group of thee triazole (i.e. ...
Lead soaps in paintings: symptoms and the role of humidity
Garrappa, Silvia; Švarcová, Silvie; Kočí, Eva; Hradilová, J.; Bezdička, Petr; Hradil, David
2020 - English
In this study, an overview of the symptoms of lead soaps reported in artworks in combination\nwith the study of the role of humidity on the formation of these degradation products have\nbeen thoroughly investigated. The use of optical microscopy, scanning electron microscopy\n(SEM) in combination with Fourier-transform infrared spectroscopy (FTIR) proved to be an\nefficient analytical approach to highlight both the saponified area of artworks’ samples and the\nformation of metal carboxylates within mock-up model systems. Optical microscopy revealed\nto be very useful for the first screening of samples embedded in resin, while SEM helped in\nthe detection and distribution of elements within the cross-sections. On the other hand, FTIR\nmicroscope proved to be a very powerful instrument for high-resolution point measurements\nperformed in the attenuated total reflection mode (ATR) mode with mercury-cadmium-telluride\n(MCT) detector, as well as for chemical imaging of larger area of both artworks’ and mock-up\nsamples performed in the ATR mode with focal plane arrays (FPA) detector. This study provides\nnew useful insights contributing to better understanding of factors affecting the paints‘ stability,\nwhich is neccesary for developing new efficient strategies for preservation and restoration of\nfatty-based painted artworks.
Keywords:
lead soaps; paintings; oil; egg yolk; humidity
Available at various institutes of the ASCR
Lead soaps in paintings: symptoms and the role of humidity
In this study, an overview of the symptoms of lead soaps reported in artworks in combination\nwith the study of the role of humidity on the formation of these degradation products have\nbeen ...
Ultrafine particles and their possible role in etiology and development of neurodegenerative diseases
Topinka, Jan; Závodná, Táňa; Rössnerová, Andrea; Rössner ml., Pavel
2020 - English
Air pollutants have been shown to cause a vast amount of different adverse health effects. These effects include impairment of many respiratory (e.g. asthma, chronic obstructive pulmonary disease) and cardiovascular (ischemic heart disease, infarction, stroke) diseases. However, in recent years, the evidence showing effects beyond the lungs and circulatory system are becoming more evident. Neurological diseases, namely Alzheimer's disease (AD) has shown to be associated with living near traffic. However, reason for this has remained unresolved until today. Our new H2020 project TUBE aims on revealing the mechanisms of action of ultrafine particles involved in neurological diseases. The TUBE consortium includes experts in areas of aerosol technology, emission research, engine and fuel research, human clinical studies, epidemiology, emission inventories, inhalation toxicology, neurotoxicology and disease mechanism studies. This enables research of resolving the effects of nanoparticles from different traffic modes for both air quality and concomitant toxic effect of these air pollutants. We will investigate adverse effects of air pollutants using cell cultures, animal exposures and volunteered human exposures as well as the material from epidemiological cohort study. These are going to be compared according to inflammatory, cytotoxic and genotoxic changes and furthermore beyond the current state of the art to neurotoxic and brain health effects. With this approach, we are aiming to a comprehensive understanding of the adverse brain effects of nanoparticles from traffic.
Keywords:
Alzheimer's disease; inflammation; neurodegenerative diseases; ultrafine particles
Available at various institutes of the ASCR
Ultrafine particles and their possible role in etiology and development of neurodegenerative diseases
Air pollutants have been shown to cause a vast amount of different adverse health effects. These effects include impairment of many respiratory (e.g. asthma, chronic obstructive pulmonary disease) and ...
The role of dispersion medium on nanoparticle aggregation and size in biological systems
Červená, Tereza; Rössnerová, Andrea; Závodná, Táňa; Vrbová, Kristýna; Sikorová, Jitka; Topinka, Jan; Rössner ml., Pavel
2020 - English
The use of nanomaterials (NMs) in different areas has been rising for more than a decade. Along with this growth, there is visible development of different testing tools and approaches for measuring the actual size of nanomaterials in biological systems. Test conditions during in vitro toxicological assays are different from the standard conditions under which nanomaterials are characterized and careful evaluation of results is needed. The unique properties and range variety of NMs require the close look how the NMs behave in different dispersion medium over time. In this study we present the results of five types of well-characterized NMs (TiO2: NM-101 and NM-103, SiO2: NM-200, Ag: NM-300K and NM-302) of specific size and shape. The hydrodynamic size and Zeta potentials in suspensions were measured using a dynamic light scattering technique (DLS) (Zetasizer Nano ZS, Malvern, UK). The DLS method is suitable for spherical particles, nevertheless, all samples were measured in order to obtain a rough insight into agglomerate formation in the medium. NM300, NM302, and NM200 aggregated rapidly in the media, thus the cells would be most likely exposed to settled big aggregates then small clusters or individual particles. More stable NMs (NM100 and NM103) showed slight grow along with cultivation time or concentration corresponding to cluster formation. Cells exposed to those NMs would be in contact with small clusters and aggregates of NMs. Measured zeta potentials fluctuated around the stability limit corresponding to observed aggregation.
Keywords:
nanomaterials; NMs; DLS; aggregation
Available at various institutes of the ASCR
The role of dispersion medium on nanoparticle aggregation and size in biological systems
The use of nanomaterials (NMs) in different areas has been rising for more than a decade. Along with this growth, there is visible development of different testing tools and approaches for measuring ...
Photon-upconversion nanoparticles for single-molecule immunosensing of cancer biomarkers and bacteria
Farka, Z.; Mickert, M. J.; Hlaváček, Antonín; Poláchová, V.; Kostiv, Uliana; Pastucha, M.; Horák, Daniel; Gorris, H. H.; Skládal, P.
2020 - English
The recent progress in the field of immunoassays has been driven by introduction of various kinds of nanomaterials. In particular, photon-upconversion nanoparticles (UCNPs) proved to be excellent immunoassay labels due to their ability to emit light of shorter wavelengths under near-infrared excitation (anti-Stokes emission), which prevents autofluorescence, minimizes light scattering, and thus reduces the optical background interference. These unique photoluminescent properties allow counting of individual biomolecules labeled with UCNPs by conventional wide-field epiluminescence microscopy and enable the development of single-molecule (digital) immunoassays. We have introduced a novel label based on UCNPs conjugated with streptavidin via poly(ethylene glycol) and applied it in a digital upconversion-linked immunosorbent assay (ULISA) for the detection of a cancer biomarker prostate specific antigen (PSA). The digital readout based on counting of individual immunocomplexes improved the sensitivity 16× compared to conventional analog readout and allowed to reach a limit of detection (LOD) of 23 fg·mL−1 (800 aM). Human serum samples were successfully analyzed achieving an excellent correlation with electrochemiluminescence reference method. The conjugates of UCNPs with streptavidin are also suitable for the detection of pathogenic bacterium Melissococcus plutonius, the causative agent of honeybee disease European foulbrood. The ULISA assay provided an LOD of 340 CFU·mL−1 and successfully analyzed real samples of bees, larvae and bottom hive debris. Due to the high reliability and relatively simple detection scheme, the digital ULISA can pave the way for a new generation of digital immunoassays with a strong potential for commercialization.
Keywords:
single-molecule detection; photon-upconversion nanoparticle; bioconjugation
Available at various institutes of the ASCR
Photon-upconversion nanoparticles for single-molecule immunosensing of cancer biomarkers and bacteria
The recent progress in the field of immunoassays has been driven by introduction of various kinds of nanomaterials. In particular, photon-upconversion nanoparticles (UCNPs) proved to be excellent ...
Chemical vapor generation of cadmium for analytical atomic spectrometry
Sagapova, Linda; Kodríková, Barbora; Svoboda, Milan; Musil, Stanislav; Kratzer, Jan
2020 - English
Chemical vapor generation of cadmium volatile compounds was optimized in order to determine trace Cd concentrations by atomic absorption spectrometry (AAS). Several reaction modifiers based on inorganic salts and complexes of CrIII+, CoII+, TiIII+, TiIV+ were tested to improve analytical performance and generation efficiency.
Keywords:
chemical vapor generation; cadmium; atomic absorption spectrometry
Available on request at various institutes of the ASCR
Chemical vapor generation of cadmium for analytical atomic spectrometry
Chemical vapor generation of cadmium volatile compounds was optimized in order to determine trace Cd concentrations by atomic absorption spectrometry (AAS). Several reaction modifiers based on ...
Tebuconazole and its behaviour in the presence of magnesium
Jakl, M.; Jaklová Dytrtová, Jana
2020 - English
Tebuconazole is a fungicide frequently used in agriculture. Its possible impact to (non-)target species is influenced by its presence. Moreover, the presence of triazoles in soil has an impact to bioavailability of nutrients. This study brings the information potentially useful in the evaluation of tebuconazole fate in the environment. The studies based on the electrospray gas phase experiments provide an estimation of the tebuconazole ability to create complexes with magnesium.
Keywords:
triazoles; Mg(II); mass spectrometry; ESI-MS; complexes
Available at various institutes of the ASCR
Tebuconazole and its behaviour in the presence of magnesium
Tebuconazole is a fungicide frequently used in agriculture. Its possible impact to (non-)target species is influenced by its presence. Moreover, the presence of triazoles in soil has an impact to ...
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