Reaction Mechanisms of Psychoactive Compounds
Sokolová, Romana; Beneš, Marek; Jiroušková, Eliška; Degano, I.
2024 - English
The reaction mechanism of selected new psychoactive substances (NPS) 4-methylpentedrone and 2-(((4-ethyl-2,5-dimethoxyphenethyl)amino)methyl)phenol was investigated based on their\nelectrochemical and spectroelectrochemical properties. Both drugs were examined by means of cyclic voltammetry using diagnostic parameters for particular reaction schemes, UV/Vis, and IR\nspectroelectrochemistry. Since water participates in the redox mechanism of both studied compounds, the reaction mechanism was studied under a controlled amount of water in an\nacetonitrile environment.
Keywords:
oxidation; reduction; IR spectrochemistry
Available on request at various institutes of the ASCR
Reaction Mechanisms of Psychoactive Compounds
The reaction mechanism of selected new psychoactive substances (NPS) 4-methylpentedrone and 2-(((4-ethyl-2,5-dimethoxyphenethyl)amino)methyl)phenol was investigated based on their\nelectrochemical and ...
Spectroelectrochemical Devices for Monitoring of Intermediates and Products on Carbonbased Composite Electrodes
Vaněčková, Eva; Šikula, M.; Hrdlička, Vojtěch; Sebechlebská, Táňa; Kolivoška, Viliam
2024 - English
Spectroelectrochemistry (SEC), as an interdisciplinary field, provides us with more comprehensive information about electroactive molecules involved in charge transfer reactions. Commercially\navailable SEC cells most often have an incorporated platinum working electrode, which can limit the range of the usable potential window and, in addition, can complicate the analysis due to the\nabsorption phenomenon. In this work, we designed and manufactured two types of custom-made SEC cells employing optically transparent carbon-based working electrodes for UV-Vis monitoring of reactants and electrogenerated intermediates and products. The first SEC cell is entirely manufactured by 3D printing using fused deposition modeling (FDM) by combining optically transparent (PET) and electrically conductive (PLA-CB) filaments. The second SEC cell employs pencil graphite (PG) rods as the working electrode (PGE) and its body is manually assembled from quartz slides. The functionality of the FDM 3D printed SEC cell and manually assembled quartz SEC cell were verified by cyclic voltammetry with in situ UV-Vis spectroscopic absorption monitoring of ruthenium(III) acetylacetonate (Ru(ac)3) redox-active probe dissolved in an aqueous or non-aqueous deaerated solvent, respectively. Both presented cells enable complete redox reversible conversion and strictly oxygen-free conditions.
Keywords:
pencil graphite electrode; spectroelectrochemistry; 3D printed electrode
Available on request at various institutes of the ASCR
Spectroelectrochemical Devices for Monitoring of Intermediates and Products on Carbonbased Composite Electrodes
Spectroelectrochemistry (SEC), as an interdisciplinary field, provides us with more comprehensive information about electroactive molecules involved in charge transfer reactions. ...
Assessment of the Presence of Hazardous Components in Textile Waste
Shtukaturova, Anastasia
2024 - English
An up-flow percolation test was chosen to identify and characterize heavy metals and PFAS constituents in textile waste. Up-flow column percolation tests are used on a laboratory scale to assess the leaching behavior of a hazardous substance from a waste in a given state as a function of time. The test was performed according to the European Technical Standard CEN/TS 14405. Preliminary results showed the following heavy metals in the leachates Al, As, Co, Cr, Cu, Fe, Mn, Pb, Zn and Sb, with Al, Cr, Fe, Mn and Zn being predominant.
Keywords:
textile waste; percolation test; PFAS; heavy metals
Available in a digital repository NRGL
Assessment of the Presence of Hazardous Components in Textile Waste
An up-flow percolation test was chosen to identify and characterize heavy metals and PFAS constituents in textile waste. Up-flow column percolation tests are used on a laboratory scale to assess the ...
Drone Based Vertical Profiling of Black Carbon Aerosols at a Rural Background and an Urban Site in Central Europe
Julaha, Kajal
2024 - English
This research aims to assess the vertical distribution of BC aerosols using a drone and micro Aethalometer AE51 at two distinct sites in the Czech Republic: 1. NAOK (National Atmospheric Observatory Košetice) representing a regional background, and 2. MFF (Faculty of Mathematics and Physics in Prague) representing an urban site. At NAOK, a 250-meter measurement tower is accessible, providing a means to validate and calibrate the drone measurements.
Available in a digital repository NRGL
Drone Based Vertical Profiling of Black Carbon Aerosols at a Rural Background and an Urban Site in Central Europe
This research aims to assess the vertical distribution of BC aerosols using a drone and micro Aethalometer AE51 at two distinct sites in the Czech Republic: 1. NAOK (National Atmospheric Observatory ...
Vertical Gradients of Atmospheric Aerosols Chemical Composition
Kovářík, Jiří
2024 - English
Concentration of chemical species chosen as markers for AA source apportionment are evaluated with regard to atmospheric conditions, seasonal and daily cycles and compared between the two heights. This work adds to the current state of general knowledge about AACC.
Keywords:
vertical gradients; chemical composition; atmospheric aerosols
Available in a digital repository NRGL
Vertical Gradients of Atmospheric Aerosols Chemical Composition
Concentration of chemical species chosen as markers for AA source apportionment are evaluated with regard to atmospheric conditions, seasonal and daily cycles and compared between the two heights. ...
Cultivation of Limnospira Maxima and Utilization of its Fresh Biomass in Human Nutrition
Vásquez, Claudia
2024 - English
This project aims to fill this gap by presenting new insights into its consumption as an alternative to dried spirulina and offering recommendations\nfor safe storage.
Keywords:
Limnospira maxima; dietary supplements; bioengineering
Available in a digital repository NRGL
Cultivation of Limnospira Maxima and Utilization of its Fresh Biomass in Human Nutrition
This project aims to fill this gap by presenting new insights into its consumption as an alternative to dried spirulina and offering recommendations\nfor safe storage.
Electrochemistry of Acetaminophen
Mikysek, T.; Ludvík, Jiří
2024 - English
The contribution is focused on electrochemical oxidation of acetaminophen mainly in non-aqueous media. The influence of various organic solvents as well as the pH effect is described herein. The redox properties of acetaminophen were studied by means of cyclic voltammetry, and rotating-disk voltammetry. We found that the protonation/deprotonation of acetaminophen acts as a ratedetermining step, where the stability of phenoxy radical intermediate plays an important role.
Keywords:
acetaminophen; phenacetine; voltammetry
Available on request at various institutes of the ASCR
Electrochemistry of Acetaminophen
The contribution is focused on electrochemical oxidation of acetaminophen mainly in non-aqueous media. The influence of various organic solvents as well as the pH effect is described herein. The redox ...
Temoporfin-conjugated upconversion nanoparticles for NIR-induced photodynamic therapy of pancreatic cancer
Shapoval, Oleksandr; Větvička, D.; Kabešová, M.; Engstová, Hana; Horák, Daniel
2024 - English
Photodynamic therapy (PDT), a clinically approved cancer treatment strategy, has the potential to cure pancreatic cancer with minimal side effects. PDT primarily uses visible wavelengths to directly activate hydrophobic photosensitizers, which may be insufficient for deep-seated cancer cells in clinical practice due to poor penetration. Upconversion nanoparticles (UCNPs) serve as an indirect excitation source to activate photosensitizers (PSs) in the NIR region, overcoming the limitations of molecular PSs such as hydrophobicity, non-specificity, and excitation in the UV/Vis region. Here, monodisperse upconversion NaYF4:Yb3+, Er3+, Fe2+ nanoparticles (UCNPs) have been surface-engineered with poly(methyl vinyl ether-alt-maleic acid) (PMVEMA) and temoporfin (mTHPC), a clinically used PDT prodrug, for near-infrared (NIR) light-triggered PDT of pancreatic cancer. The incorporation of Fe2+ ions into the particles increased the fluorescence intensity in the red region matching the activation wavelength of mTHPC. Covalent binding of mTHPC to the surface of UCNP@PMVEMA particles provided colloidally stable conjugates enabling generation of singlet oxygen. In vitro cytotoxicity and photodynamic activity of the particles were evaluated using INS-1E rat insulinoma and Capan-2 and PANC-01 human pancreatic adenocarcinoma cell lines. The PDT efficacy of UCNP@PMVEMA-mTHPC conjugates after irradiation with 980 nm NIR light was tested in vivo in a pilot study on Capan-2 human pancreatic adenocarcinoma growing subcutaneously in athymic nude mice. The intratumoral administration of the nanoconjugates significantly hindered tumor growth and demonstrated promising PDT efficacy against human pancreatic cancer.
Keywords:
photodynamic therapy; temoporfin; upconversion nanoparticles
Available in digital repository of the ASCR
Temoporfin-conjugated upconversion nanoparticles for NIR-induced photodynamic therapy of pancreatic cancer
Photodynamic therapy (PDT), a clinically approved cancer treatment strategy, has the potential to cure pancreatic cancer with minimal side effects. PDT primarily uses visible wavelengths to directly ...
A New Approach to Determining the Drug Guaifenesin Using Voltammetric and Flow Injection Analysis
Kelíšková, P.; Matvieiev, O.; Sokolová, Romana; Janíková, L.; Behúl, M.; Šelešovská, R.
2024 - English
This study presents a new method for detecting guaifenesin (GFE) in pharmaceutical samples. We employed screen-printed sensors with a boron-doped diamond electrode (BDDE) to develop and validate both voltammetric and flow amperometric methods. These approaches were effectively used to analyze model solutions, pharmaceutical preparations, and serum samples spiked with GFE, producing accurate results comparable to those obtained with HPLC/DAD analysis. The developed methods provide straightforward, sensitive, and selective means for determining GFE in various sample matrices, underscoring the potential of SP/BDDE in electrochemical analysis.
Keywords:
guaifenesin; screen-printed sensor; boron-doped diamond electrode
Available on request at various institutes of the ASCR
A New Approach to Determining the Drug Guaifenesin Using Voltammetric and Flow Injection Analysis
This study presents a new method for detecting guaifenesin (GFE) in pharmaceutical samples. We employed screen-printed sensors with a boron-doped diamond electrode (BDDE) to develop and validate both ...
Optimization of Parameters Used in the Application of Elimination Voltammetry with Linear Scan
Navrátil, Tomáš; Trnková, L.; Hrdlička, Vojtěch; Li, X.
2024 - English
Elimination Voltammetry with Linear Scan (EVLS) is a well-established mathematical method that aids in understanding an analyzed electrochemical system. In almost 30 years since its derivation, it has become a “black-box” technique that is applied automatically (in most cases due to its incorporation into a voltammetric software) without thinking about its fundamentals. However, the choice of optimum parameters under which DC voltammetric data (from which elimination curves are calculated) is crucial. This contribution deals with revealing the optimum ratio of applied scan rates and their absolute values (i.e., times of recording) in dependence on the character of the investigated system (diffusion-controlled process, adsorption-controlled process, etc.).
Keywords:
elimination voltammetry with linear scan; optimization; adsorption
Available on request at various institutes of the ASCR
Optimization of Parameters Used in the Application of Elimination Voltammetry with Linear Scan
Elimination Voltammetry with Linear Scan (EVLS) is a well-established mathematical method that aids in understanding an analyzed electrochemical system. In almost 30 years since its derivation, it has ...
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