No (6903)
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6903
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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 ...
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 ...
Application of In situ TR Spectroelectrochemical Techniques in Determination of Redox Mechanism of Bioactive Compounds
Sokolová, Romana; Jiroušková, Eliška; Degano, I.; Wantulok, J.; Nycz, J.
2023 - English
The electron transfer reactions play an important role in many natural processes. Reactions such as \ndissociation, protonation, and reactions with water and other small molecules often occur in \nbiotransformation. The reaction schemes involving these chemical reactions coupled to the \nelectron transfer can be determined by cyclic voltammetry. Additionally, in \nsitu spectroelectrochemistry can efficiently contribute to the determination of oxidation or \nreduction mechanism. This technique provides information about the electroactive chromophore during \nthe redox process allowing to identification the first reaction intermediates. The final reaction \nproducts were identified by chromatographic techniques. This study represents a key role of TR \nspectroelectrochemistry in the determination of reaction intermediates in the case of \n1,10- phenanthroline derivative substituted by bioactive phenothiazine unit and \ndrug 3- fluorophenmetrazine (2-(3-fluorophenyl)-3-methylmorpholine, 3-FPM). Co pound 3-FPM\nhave recently appeared as the new psychoactive substance in the drug market.\n
Keywords:
IR spectroelectrochemistry; psychoactive substances; oxidation mechanism
Available on request at various institutes of the ASCR
Application of In situ TR Spectroelectrochemical Techniques in Determination of Redox Mechanism of Bioactive Compounds
The electron transfer reactions play an important role in many natural processes. Reactions such as \ndissociation, protonation, and reactions with water and other small molecules often occur in ...
A polarizable reference electrode
Mareček, Vladimír
2023 - English
New concept of a reference electrode for electrochemical systems resolves a problem of a poor \npotential stability of refence electrodes based on the distribution of a strongly \nhydrophobic common cation between two immiscible electrolyte solutions (TTTES). The use of a \npolarizable metal electrode instead of a classical reference electrode is demonstrated in \n a modified conventional four-electrode cell with TTTES. A simple battery operated potentiostat \ncontrols the working electrode potential in a three-electrode configuration. The working metal \nelectrode then serves as a polarizable reference organic solvent electrode in a four-electrode \nsystem for the polarization of the water/organic solvent interface.\n\n
Keywords:
reference electrode; liquid/liquid interface; chloride extraction
Available on request at various institutes of the ASCR
A polarizable reference electrode
New concept of a reference electrode for electrochemical systems resolves a problem of a poor \npotential stability of refence electrodes based on the distribution of a strongly ...
Electrochemically Investigated pH-dependent Redox Properties of Copper Complexes of Azamacrocyclic Ligands
Koláčná, Lucie; Maďar, M.; Kubíček, V.; Ludvík, Jiří
2023 - Czech
Investigated Cu(II) complexes are based on plain or cross-bridged cyclam. The\nelectrochemically inactive cyclam was modified by carboxylate, phosphonate, or phenolate\npendant arms. Cu(II) represents the main redox center of the complexes. Modification of the\nligand causes a changed pattern of complex redox response in buffered aqueous solution.\nIrreversible Cu(II) reduction results in complex decomposition to amalgamated copper and\nligand in excess. After Cu(0) electrochemical in situ re-oxidation, copper and ligand are recomplexed.\nComplexes undergo isomerization, accelerated by increasing the temperature. The\ninfluence of pH on complex isomerization and the reversibility of its reduction was described. Molekulární elektronika je progresivní směr moderní materiálové chemie. Zabývá se vývojem\nelektronických prvků na úrovni jedné molekuly. Nejdůmyslnější molekulární elektroniku\nnajdeme v přírodě v podobě metaloenzymů. Jedním ze směrů výzkumu jejich modelů jsou\nkomplexy různě substituovaných azamakrocyklů. Předností těchto molekul je jejich stabilita a\ndobře definovaná syntéza.
Keywords:
cyclam; Cu(II) complexes; pendant arms
Available on request at various institutes of the ASCR
Electrochemically Investigated pH-dependent Redox Properties of Copper Complexes of Azamacrocyclic Ligands
Investigated Cu(II) complexes are based on plain or cross-bridged cyclam. The\nelectrochemically inactive cyclam was modified by carboxylate, phosphonate, or phenolate\npendant arms. Cu(II) represents ...
Determination of Selected Natural Psychoactive Substances in Organic Matrices at 3D Printed Electrodes
Choińska-Mlynarczyk, Marta; Šestáková, Ivana; Navrátil, Tomáš
2023 - English
Psilocybin and its derivative psilocin are popular psychoactive substances both as experimental\ntreatments in clinical trials and as illicit drugs. Their potential ability to influence the human\nbrain entails the need for a fast, inexpensive, selective, and sensitive method of their\ndetermination. The aim of our study was the development of new 3D-printed electrodes which\nfulfill these demands and are useful for medical, toxicological, and forensic purposes.\nSuccessful development allows determining in real matrices (human plasma and dried\nmushrooms) concentrations of the order of 1 μmol dm-3.\n
Keywords:
natural psychoactive substances; 3D-printed electrodes; psilocin; psilocybin
Available on request at various institutes of the ASCR
Determination of Selected Natural Psychoactive Substances in Organic Matrices at 3D Printed Electrodes
Psilocybin and its derivative psilocin are popular psychoactive substances both as experimental\ntreatments in clinical trials and as illicit drugs. Their potential ability to influence the ...
Proceedings of 24th School of Mass Spectrometry
Cvačka, Josef; Vlk, Mikuláš; Vrkoslav, Vladimír; Hubálek, Martin
2023 - Czech
Keywords:
mass spectrometry; LC-MS; GC-MS
Available at various institutes of the ASCR
Proceedings of 24th School of Mass Spectrometry
Biopharmaceuticals from the MS point of view
Hubálek, Martin; Lenčo, J.
2023 - Czech
The course aims to introduce biotherapeutics, which are becoming an increasingly important part of the pharmacotherapy of serious diseases. Mass spectrometry plays an important role for their quality control in the pharmaceutical industry. We will introduce the audience to biopharmaceuticals, which in this context are peptides, proteins, monoclonal antibodies or oligonucleotides. From the analyst's point of view, we will focus mainly on antibody drugs, looking at the possibilities of their separation and analysis by mass spectrometry, at the level of intact protein molecules, antibody subunits or peptides. Kurz má za cíl představit bioléčiva, která se stávají stále významnější součástí farmakoterapie závažných onemocnění. Pro kontrolu jejich kvality ve farmaceutickém průmyslu hraje důležitou roli hmotnostní spektrometrie. Uvedeme posluchače do problematiky bioléčiv, kterými jsou v tomto pohledu peptidy, proteiny, monoklonální protilátky nebo oligonukleotidy. Z pohledu analytika se zaměříme především na protilátková léčiva, podíváme se na možnosti jejich separace a analýzy pomocí hmotnostní spektrometrie, a to na úrovni intaktních proteinových molekul, protilátkových podjednotek nebo peptidů.
Keywords:
mass spectrometry; biopharmaceuticals; LC-MS
Available on request at various institutes of the ASCR
Biopharmaceuticals from the MS point of view
The course aims to introduce biotherapeutics, which are becoming an increasingly important part of the pharmacotherapy of serious diseases. Mass spectrometry plays an important role for their quality ...
24th School of Mass Spectrometry. Course D - LC-MS Troubleshooting
Cvačka, Josef; Vlk, Mikuláš; Vrkoslav, Vladimír; Hubálek, Martin
2023 - Czech
Keywords:
mass spectrometry; liquid chromatography; troubleshooting
Available on request at various institutes of the ASCR
24th School of Mass Spectrometry. Course D - LC-MS Troubleshooting
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