No (5624)
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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 ...
Rozdíly v elektrochemické redukci jedno- a vícejaderných acylgermanů
Liška, Alan; Frühwirt, P.; Haas, M.; Ludvík, Jiří; Gescheidt-Demmer, G.
2021 - Czech
Acylgermany představují pestrou třídu organoprvkových sloučenin, které se vyznacuJI\npozoruhodnými fotochemickými vlastnostmi, laditelnými zavedením různých typů periferních\nsubstituentů, jejich počtem, polohou, případně způsobem přemostění. Většina známých\nderivátů podléhá vlivem DV-záření nebo dokonce krátkovlnějšího viditelného světla\nhomolytickému štěpení vazby C-Ge za vzniku radikálů. Některé (např. Ivocerin®) se proto již\ndelší dobu používají v zubní medicíně jako fotoiniciátory polymerizace při přípravě bílých\nnetoxických zubních výplní. Příslušné mechanismy reakcí uplatňujících se v praxi jsou v\nliteratuře dobře dokumentovány. Vzhledem k tomu, že penetrační hloubka\nelektromagnetického záření je nepřímo úměrná jeho energii, existuje snaha nalézt další\nderiváty, které budou efektivně štěpeny světlem o co největší vlnové délce. Kromě absorpčních\nspekter a teoretických výpočtů molekulových vlastností (ionizační energie, elektronové\nafinity) se při hledání nových látek s výhodou uplatňují elektrochemické metody, protože\npoloha prvního redukčního potenciálu (resp. rozdíl mezi prvním redukčním a prvním\noxidačním potenciálem) koreluje se schopností molekuly absorbovat světlo a zaujímat vyšší\nexcitované stavy, což se projeví jako poloha dlouhovlnného pásu UV-vis spekter. Ail the studied compounds accept first electron under formation a stable anion radical. The\ncorresponding reduction potentials in aprotic media depend on electronic (inductive,\nmesomeric) properties of the substituents, their number, and position. Here, aromatic acyl group\n(benzoyl group with various substitution on aromatic ring) is the principal substituent. The\nredox properties of presented organoelement compounds with central heteroatom Ge (Si, Sn)\nare controlled by peripheral carbonyl groups (in role of redox centers), their number, and\naromatic ring substitution. The measured first reduction potentials E1 values are found in wide\nrange (> 900 mV) due to the fact that the redox centers are carbony 1 groups connected through\nheteroatom in case of acylgermanes, while for di- and trinuclear derivatives (which are\nmolecules with multiple redox centers) the easiest reducible center is the bridging aromatic unit\ninfluenced by the closest carbonyl groups. Thus, it is possible to distinguish both groups ofnonequivalent\ncarbonyl substituents.
Keywords:
Acylgermanes; Electrochemistry; Voltammetry
Available on request at various institutes of the ASCR
Rozdíly v elektrochemické redukci jedno- a vícejaderných acylgermanů
Acylgermany představují pestrou třídu organoprvkových sloučenin, které se vyznacuJI\npozoruhodnými fotochemickými vlastnostmi, laditelnými zavedením různých typů periferních\nsubstituentů, jejich ...
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 ...
Trophic and Hydric Soil Series in the Floodplain of Natural Submountain Gravel-Carrying Moravka River in the Outer Western Carpathians
Rychtecká, P.; Rosíková, J.; Samec, Pavel
2020 - Czech
Klasifikace půdních řad je základním přístupem pro hodnocení vztahů\nmezi půdními podmínkami a vegetací. V této studii bylo situováno hodnocení půdní řady\ndo přirozeně zalesněné vněkarpatské štěrkonosné nivy podél řeky Morávky\n(336–383 m n. m., Česká republika). Klasifikace byla provedena geobiocenologicky společností\ntrofické a hydrické řady na fluviálních formách (FL) barů a aktivních až terasových nivách\npři využití intervalů pedochemických a hydrofyzikálních vlastností. Rozdíly mezi\nvlastnosti půdy na FL byly hodnoceny pomocí analýzy rozptylu a diskriminační analýzy.\nFL prokazatelně rozdělily půdní podmínky. Celková oddělitelnost trofické řady byla 84 %\nzatímco oddělitelnost hydrické řady byla 72 %. Oddělitelnost pedochemických vlastností\nbylo 66–81 % mezi FL, ačkoli hydrofyzikální vlastnosti je odlišovaly pouze s\n41-64% přesnost. Barové půdní podmínky byly na rozdíl od teras základní a hydraulicky omezené.\nAktivní záplavové území bylo založeno na necelých 68 % plochy, jinak tam byly\nmezotrofně-bázové podmínky. Půdní podmínky na terasové nivě se výrazně lišily\nmezi ornicí a podložím. Zatímco podloží bylo převážně mezotrofní (58 %) to\nmezotrofně-nitrofilní (40,5 %), ornice byla převážně mezotrofně-nitrofilní.\nSérie lužních půd byly lépe hodnotitelné prostřednictvím pedochemických vlastností než hydrofyzikální. Poměr C/N a pH/H2O ovlivnily trofickou separabilitu více než sorpci půdy.\nRozpor mezi bazickou saturací a kapacitou výměny kationtů naznačoval vývoj půdy\nintenzita na FL. Hydrické řady nivy byly zjistitelné maximální kapilární kapacitou půdy,\nkapacita zadržování vody a provzdušňování. Přechodné jevy v půdní řadě mezi mřížemi a terasou\nlužní indi The soil series classification is the fundamental approach for the evaluation of relations between soil conditions and vegetation. In this study, the evaluation of the soil series was situated into the naturally forested Outer Carpathian gravel-carrying floodplain along the Moravka River (336383 m a.s.l., Czech Republic). The classification was carried out geobiocoenologically by the trophic and hydric series on the fluvial landforms (FLs) of bars and the active to terrace floodplains under using of the pedochemical and hydro-physical properties intervals. The differences among the soil properties on the FLs were evaluated using the analysis of variance and discrimination analysis. The FLs divided the soil conditions demonstrably. Total separability of the trophic series was 84% while separability of the hydric series was 72%. The separabilities of the pedochemical properties were 6681% among the FLs although the hydro-physical properties distinguished them only with 41-64% accuracy. The bar soil conditions were base and hydrically limited in contrast to the terraces. The active floodplain was base on less than 68% of the area, otherwise there were the mesotrophicallybase conditions. The soil conditions on the terrace floodplain patently differed between the topsoil and subsoil. While the subsoil was predominantly mesotrophic (58%) to mesotrophically-nitrophilous (40.5%), the topsoil was mesotrophically-nitrophilous predominantly.
Keywords:
submountain floodplain; terrace floodplain; soil cation exchange capacity; water-holding capacity
Available at various institutes of the ASCR
Trophic and Hydric Soil Series in the Floodplain of Natural Submountain Gravel-Carrying Moravka River in the Outer Western Carpathians
Klasifikace půdních řad je základním přístupem pro hodnocení vztahů\nmezi půdními podmínkami a vegetací. V této studii bylo situováno hodnocení půdní řady\ndo přirozeně zalesněné vněkarpatské ...
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 ...
Respirace půdy smrkového porostu v průběhu čtyř let po aplikaci různých dávek vápnitého dolomitu
Rosíková, J.; Dařenová, Eva; Kučera, A.
2020 - Czech
Studie se zaměřuje na in situ odezvu půdního dýchání při 10 ° C (R10) monokultury smrku norského na aplikaci různých dávek dolomitického vápence (0, 2, 3, 4, 6, 9 a 26 t.ha- 1) po dobu čtyř let. Dýchání půdy bylo měřeno během vegetačních období 2016 - 2019. Kromě toho bylo pH stanoveno v horizontech H a Ah během každé sezóny. Účinek vápnění na dýchání v půdě byl statisticky významný během všech ročních období s výjimkou roku 2017. Největší účinek byl pozorován v první sezóně po vápnění. V květnu 2016 vzrostl R10 na pozemcích s vápnem až o 97% ve srovnání s těmi bez vápna. Půdní dýchání se však přímo úměrně s intenzitou vápnění nezvyšovalo. Zjistili jsme korelaci mezi půdním dýcháním a mikrometeorologickými parametry (teplota a vlhkost), když obě nízkoteplotní vlhkost omezovaly dýchání v půdě. Vzhledem k silné schopnosti pufrovat půdu byl v první studijní sezóně pozorován malý účinek vápnění na kyselost půdy. V následujících sezónách se rozdíly v pH mezi plochami s různou intenzitou vápnění začaly zvyšovat, což však bylo pozorováno pouze v horizontu H. Podstatné zvýšení půdní mikrobiální aktivity doprovázené rychlejším dýcháním po vápnění může vést ke zvýšené hrozbě rychlé mineralizace a ztrátě půdní organické hmoty se všemi jejími negativními dopady\n The study focuses on an in situ response of soil respiration at 10 °C (R10) of the Norway spruce monoculture to the application of the different dolomitic limestone dosages (0, 2, 3, 4, 6, 9 a 26 t.ha-1) over a period of four years. Soil respiration was measured within the growing seasons 2016 – 2019. Moreover, the pH was determined in the H and Ah horizons during each season. The effect of liming on soil respiration was statistically significant during all the seasons except for 2017. The greatest effect was observed within the first season after liming. In May 2016, R10 in the limed plots increased as much as by 97% compared to the non-limed ones. However, soil respiration did not increase in the direct proportion to the liming intensity. We found out the correlation between soil respiration and the micrometeorological parameters (temperature and moisture) when both low temperature moisture limited soil respiration. Due to the strong soil buffering capacity, the small effect of liming on the soil acidity was observed in the first study season. In the following seasons, the differences in the pH among the plots with the different liming intensity started to increase, which was, however, observed only in the H horizon. The substantial increase in the soil microbial activity accompanied with faster respiration after liming can lead to the increased threat of rapid mineralization and the loss of soil organic matter with all its negative impacts
Keywords:
mineralization; r10; liming; ph; picea abies
Available at various institutes of the ASCR
Respirace půdy smrkového porostu v průběhu čtyř let po aplikaci různých dávek vápnitého dolomitu
Studie se zaměřuje na in situ odezvu půdního dýchání při 10 ° C (R10) monokultury smrku norského na aplikaci různých dávek dolomitického vápence (0, 2, 3, 4, 6, 9 a 26 t.ha- 1) po dobu čtyř let. ...
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