Pub Date : 2024-06-21DOI: 10.1134/s1061934824700047
E. R. Salimgareeva, E. L. Gerasimova, A. V. Karmanova, K. K. Salikova, S. Yu. Saraeva, A. V. Ivanova
Abstract
The approach for the determination of antioxidants of various hydrophilicity using the complex of the iron(III) with bipyridine as a model oxidizing agent and chronoamperometric recording of the analytical signal is proposed. The choice of the oxidant is determined by its solubility in aqueous, organic and aqueous-organic media. The conditions for recording chronoamperograms are selected: the medium is the acetonitrile-acetate buffer solution (pH 3.6) (9 : 1), the electrolyte is the LiClO4, the potential is E = 1.25 V, the current registration time is 80 s. Antioxidants soluble in organic and aqueous-organic media are studied: α-tocopherol, quercetin, catechin, and caffeic acid. The analytical ranges are (0.5−4) × 10–4 M. The antioxidant capacity (AOC) of ethanol extracts from medicinal plant materials is determined. A high correlation is observed between the AOC values obtained by the chronoamperometric and the spectrophotometric approaches, but only for samples whose intrinsic colors do not contribute to the absorbance of the Fe(II)-bipyridine complex. The application of the proposed approach and the potentiometric method using the K3[Fe(CN)6]/K4[Fe(CN)6] system showed that the values obtained by the potentiometric approach are significantly lower for most of the studied infusions. Thus, it is advisable to analyze multicomponent objects, containing substances of different hydrophilicity, using approaches with oxidizing agents of different solubilities, such as the Fe(III)-bipyridine complex.
{"title":"Chronoamperometric Determination of Antioxidant Capacity Using an Iron Complex with 2,2'-Bipyridine","authors":"E. R. Salimgareeva, E. L. Gerasimova, A. V. Karmanova, K. K. Salikova, S. Yu. Saraeva, A. V. Ivanova","doi":"10.1134/s1061934824700047","DOIUrl":"https://doi.org/10.1134/s1061934824700047","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The approach for the determination of antioxidants of various hydrophilicity using the complex of the iron(III) with bipyridine as a model oxidizing agent and chronoamperometric recording of the analytical signal is proposed. The choice of the oxidant is determined by its solubility in aqueous, organic and aqueous-organic media. The conditions for recording chronoamperograms are selected: the medium is the acetonitrile-acetate buffer solution (pH 3.6) (9 : 1), the electrolyte is the LiClO4, the potential is <i>E</i> = 1.25 V, the current registration time is 80 s. Antioxidants soluble in organic and aqueous-organic media are studied: α-tocopherol, quercetin, catechin, and caffeic acid. The analytical ranges are (0.5−4) × 10<sup>–4</sup> M. The antioxidant capacity (<b>AOC</b>) of ethanol extracts from medicinal plant materials is determined. A high correlation is observed between the AOC values obtained by the chronoamperometric and the spectrophotometric approaches, but only for samples whose intrinsic colors do not contribute to the absorbance of the Fe(II)-bipyridine complex. The application of the proposed approach and the potentiometric method using the K<sub>3</sub>[Fe(CN)<sub>6</sub>]/K<sub>4</sub>[Fe(CN)<sub>6</sub>] system showed that the values obtained by the potentiometric approach are significantly lower for most of the studied infusions. Thus, it is advisable to analyze multicomponent objects, containing substances of different hydrophilicity, using approaches with oxidizing agents of different solubilities, such as the Fe(III)-bipyridine complex.</p>","PeriodicalId":606,"journal":{"name":"Journal of Analytical Chemistry","volume":"16 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141507481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-21DOI: 10.1134/s1061934824700060
I. A. Abramov, S. I. Gainanova, L. R. Zagitova, V. N. Maistrenko
Abstract
Antibacterial drugs have become an integral part of the food industry and agriculture in the present-day world. The presence of even trace amounts of antibiotics in foods of animal origin can lead to the development of allergic reactions and direct toxic effects in a human body. In this regard, it is necessary to create sensitive and selective procedures for determining antibacterial drugs in order to prevent their excessive consumption. In this work, a glassy carbon voltammetric sensor based on layer-by-layer deposited electroreduced graphene oxide and fullerene functionalized with S-N,N'-bis(1-phenylethyl)malonamide is proposed for the determination of levofloxacin (Lev, S-(-)-ofloxacin) by differential pulse voltammetry. The calibration graph is linear in two ranges, 1.0 × 10–6–6.0 × 10–5 M and 6.0 × 10–5–5.0 × 10–4 M Lev, with sensitivity coefficients of 107 and 58.0 μA/mM, respectively. The limit of detection and limit of quantification are 1.8 × 10–7 and 6.04 × 10–7 M, respectively. The selectivity of the sensor to Lev relative to some fluoroquinolone antibiotics: ciprofloxacin, lomefloxacin, and enrofloxacin, was assessed. The sensor was used to determine Lev in meat and milk using differential pulse voltammetry.
摘要 抗菌药物已成为当今世界食品工业和农业不可或缺的一部分。动物源性食品中即使含有微量的抗生素，也会导致过敏反应的发生，并对人体产生直接的毒性作用。因此，有必要建立灵敏且有选择性的抗菌药物测定程序，以防止抗菌药物的过度消费。本研究提出了一种基于逐层沉积电还原氧化石墨烯和富勒烯的玻璃碳伏安传感器，该传感器由 S-N,N'-双(1-苯基乙基)丙二酰胺功能化，通过差分脉冲伏安法测定左氧氟沙星（Lev，S-(-)-ofloxacin）。在 1.0 × 10-6-6.0 × 10-5 M 和 6.0 × 10-5-5.0 × 10-4 M Lev 两个范围内，校准图呈线性关系，灵敏度系数分别为 107 和 58.0 μA/mM。检测限和定量限分别为 1.8 × 10-7 M 和 6.04 × 10-7 M。评估了该传感器相对于一些氟喹诺酮类抗生素（环丙沙星、洛美沙星和恩诺沙星）对 Lev 的选择性。该传感器被用于使用差分脉冲伏安法测定肉类和牛奶中的 Lev 含量。
{"title":"Voltammetric Determination of Levofloxacin in Meat and Milk Using a Sensor Based on Electroreduced Graphene Oxide and Functionalized Fullerene","authors":"I. A. Abramov, S. I. Gainanova, L. R. Zagitova, V. N. Maistrenko","doi":"10.1134/s1061934824700060","DOIUrl":"https://doi.org/10.1134/s1061934824700060","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Antibacterial drugs have become an integral part of the food industry and agriculture in the present-day world. The presence of even trace amounts of antibiotics in foods of animal origin can lead to the development of allergic reactions and direct toxic effects in a human body. In this regard, it is necessary to create sensitive and selective procedures for determining antibacterial drugs in order to prevent their excessive consumption. In this work, a glassy carbon voltammetric sensor based on layer-by-layer deposited electroreduced graphene oxide and fullerene functionalized with <i>S-N</i>,<i>N</i>'-bis(1-phenylethyl)malonamide is proposed for the determination of levofloxacin (<b>Lev</b>, S-(-)-ofloxacin) by differential pulse voltammetry. The calibration graph is linear in two ranges, 1.0 × 10<sup>–6</sup>–6.0 × 10<sup>–5</sup> M and 6.0 × 10<sup>–5</sup>–5.0 × 10<sup>–4</sup> M Lev, with sensitivity coefficients of 107 and 58.0 μA/mM, respectively. The limit of detection and limit of quantification are 1.8 × 10<sup>–7</sup> and 6.04 × 10<sup>–7</sup> M, respectively. The selectivity of the sensor to Lev relative to some fluoroquinolone antibiotics: ciprofloxacin, lomefloxacin, and enrofloxacin, was assessed. The sensor was used to determine Lev in meat and milk using differential pulse voltammetry.</p>","PeriodicalId":606,"journal":{"name":"Journal of Analytical Chemistry","volume":"40 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141529665","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-21DOI: 10.1134/s1061934824700175
Nafisur Rahman, Shahroora Sameen, Mohammad Kashif, Mohd Nasir
Abstract
A sensitive spectrofluorimetric method was developed to determine trazodone hydrochloride in its formulation and urine sample. The principle of the developed method is based on the formation of an ion pair complex at a pH of 4.27 between the analyte drug and eosin Y, followed by its extraction into dichloromethane and subsequent fluorescence measurement. The fluorescence of the extracted trazodone-eosin Y complex was recorded at 450 nm with an excitation wavelength of 350 nm. Recording the fluorescence was utilized to construct the calibration plot, which was found to be linear in the range of 32.0–1.50 × 103 ng/mL of trazodone hydrochloride. The influences of experimental variables, namely pH, volumes of eosin Y (2.90 × 10–3 M), and buffer solution (pH 4.27), on the fluorescence intensity were examined and optimized by response surface methodology via Box−Behnken design. The limits of detection and the limit of quantitation of the reported method are 9.50 and 28.79 ng/mL, respectively. The accuracy of the proposed method was evaluated for intra-day and inter-day precision in the range of 0.46 to 0.77% RSD. The content of trazodone hydrochloride in its dosage forms was determined by the developed method using the standard addition technique, and the results showed good recovery between 96.50 and 99.25%, with a standard analytical error of 1.54 × 10–5 to 2.86 × 10–4. Interval hypothesis testing confirmed that it is lower than ±2%; hence, there was no bias between the developed and reference methods. No interference was observed from the common excipients present in tablet formulations. The developed method was also successfully applied for the determination of trazodone in urine samples, and recovery of the drug was observed in the range of 90–98%.
{"title":"Statistical Design Approach for Optimizing the Spectrofluorimetric Method for Quantifying Trazodone Hydrochloride","authors":"Nafisur Rahman, Shahroora Sameen, Mohammad Kashif, Mohd Nasir","doi":"10.1134/s1061934824700175","DOIUrl":"https://doi.org/10.1134/s1061934824700175","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>A sensitive spectrofluorimetric method was developed to determine trazodone hydrochloride in its formulation and urine sample. The principle of the developed method is based on the formation of an ion pair complex at a pH of 4.27 between the analyte drug and eosin Y, followed by its extraction into dichloromethane and subsequent fluorescence measurement. The fluorescence of the extracted trazodone-eosin Y complex was recorded at 450 nm with an excitation wavelength of 350 nm. Recording the fluorescence was utilized to construct the calibration plot, which was found to be linear in the range of 32.0–1.50 × 10<sup>3</sup> ng/mL of trazodone hydrochloride. The influences of experimental variables, namely pH, volumes of eosin Y (2.90 × 10<sup>–3</sup> M), and buffer solution (pH 4.27), on the fluorescence intensity were examined and optimized by response surface methodology via Box−Behnken design. The limits of detection and the limit of quantitation of the reported method are 9.50 and 28.79 ng/mL, respectively. The accuracy of the proposed method was evaluated for intra-day and inter-day precision in the range of 0.46 to 0.77% RSD. The content of trazodone hydrochloride in its dosage forms was determined by the developed method using the standard addition technique, and the results showed good recovery between 96.50 and 99.25%, with a standard analytical error of 1.54 × 10<sup>–5</sup> to 2.86 × 10<sup>–4</sup>. Interval hypothesis testing confirmed that it is lower than ±2%; hence, there was no bias between the developed and reference methods. No interference was observed from the common excipients present in tablet formulations. The developed method was also successfully applied for the determination of trazodone in urine samples, and recovery of the drug was observed in the range of 90–98%.</p>","PeriodicalId":606,"journal":{"name":"Journal of Analytical Chemistry","volume":"14 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141525833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-21DOI: 10.1134/s1061934824700205
Marianela Zoratti, Marisa Alejandra Frechero, María Eugenia Centurión
Abstract
A new modified electrode was developed employing an environmentally friendly method to be used in a square-wave voltammetry technique, with advantages such as low cost, rapid response, and high sensitivity, to determine iron in milk powder samples. For this purpose, a novel lab-made electrode based on a borate glassy matrix, doped with molybdenum, lithium, and vanadium oxides, and surface modified with carbon nanoparticles was synthesized. The glassy matrix was obtained by the quenching methodology and the carbon nanoparticles were synthesized using microwave-assisted method and honey as a precursor. The voltammetric behavior of the proposed electrode was evaluated with a potassium hexacyanoferrate(II) solution. Moreover, since iron plays an important role in human nutrition, its quantification in fortified powder milk analysis employing the proposed electrode and square-wave voltammetry was studied. The linear response of iron concentration was in the range of 0.3 to 5.9 mg/L with a limit of detection of 0.18 mg/L. The iron content in the proposed method is in accordance with the inductively coupled plasma atomic emission spectroscopy values and those declared on the label. This electrochemical sensor shows great potential for the determination of iron in food samples and it can be incorporated into a portable device for in situ detection of this analyte.
{"title":"Voltammetric Sensor Based on Molybdenum-Vanadium-Lithium-Borate Glassy Matrix and Its Application for the Determination of Iron in Fortified Milk Powder","authors":"Marianela Zoratti, Marisa Alejandra Frechero, María Eugenia Centurión","doi":"10.1134/s1061934824700205","DOIUrl":"https://doi.org/10.1134/s1061934824700205","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>A new modified electrode was developed employing an environmentally friendly method to be used in a square-wave voltammetry technique, with advantages such as low cost, rapid response, and high sensitivity, to determine iron in milk powder samples. For this purpose, a novel lab-made electrode based on a borate glassy matrix, doped with molybdenum, lithium, and vanadium oxides, and surface modified with carbon nanoparticles was synthesized. The glassy matrix was obtained by the quenching methodology and the carbon nanoparticles were synthesized using microwave-assisted method and honey as a precursor. The voltammetric behavior of the proposed electrode was evaluated with a potassium hexacyanoferrate(II) solution. Moreover, since iron plays an important role in human nutrition, its quantification in fortified powder milk analysis employing the proposed electrode and square-wave voltammetry was studied. The linear response of iron concentration was in the range of 0.3 to 5.9 mg/L with a limit of detection of 0.18 mg/L. The iron content in the proposed method is in accordance with the inductively coupled plasma atomic emission spectroscopy values and those declared on the label. This electrochemical sensor shows great potential for the determination of iron in food samples and it can be incorporated into a portable device for in situ detection of this analyte.</p>","PeriodicalId":606,"journal":{"name":"Journal of Analytical Chemistry","volume":"59 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141525836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-21DOI: 10.1134/s1061934824700096
L. G. Shaidarova, I. A. Chelnokova, D. A. Koryakovtseva, D. A. Kirilenko, H. C. Budnikov
Abstract
It is found that mixed-valence iridium oxides electrodeposited on the surface of a glassy carbon electrode exhibit catalytic activity in the oxidation of caffeine. In this case, a more pronounced catalytic effect is obtained on an electrode modified with a composite based on a film of a perfluorinated sulfopolymer (Nafion) and mixed-valence iridium oxides. A selective voltammetric method for the determination of caffeine is developed. A linear logarithmic dependence of current on the caffeine concentration is observed in the range from 1 × 10–8 to 5 × 10–3 M. The developed method was used to determine caffeine in energy drinks.
{"title":"Voltammetric Determination of Caffeine in Energy Drinks Using an Electrode Modified with a Nafion Film and Mixed-Valence Iridium Oxides","authors":"L. G. Shaidarova, I. A. Chelnokova, D. A. Koryakovtseva, D. A. Kirilenko, H. C. Budnikov","doi":"10.1134/s1061934824700096","DOIUrl":"https://doi.org/10.1134/s1061934824700096","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>It is found that mixed-valence iridium oxides electrodeposited on the surface of a glassy carbon electrode exhibit catalytic activity in the oxidation of caffeine. In this case, a more pronounced catalytic effect is obtained on an electrode modified with a composite based on a film of a perfluorinated sulfopolymer (Nafion) and mixed-valence iridium oxides. A selective voltammetric method for the determination of caffeine is developed. A linear logarithmic dependence of current on the caffeine concentration is observed in the range from 1 × 10<sup>–8</sup> to 5 × 10<sup>–3</sup> M. The developed method was used to determine caffeine in energy drinks.</p>","PeriodicalId":606,"journal":{"name":"Journal of Analytical Chemistry","volume":"43 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141525828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-21DOI: 10.1134/s1061934824700126
V. Shavokshina, A. Okoneshnikov, V. Nikitina, A. Karyakin
Abstract
Flow injection amperometry provides an opportunity to avoid common drawbacks of classical potentiometry for solid-contact ion-selective electrodes. The current is generated by solid-contact in course of the polymer chain recharging in response to an excess of cations or anions in the polymer film. Cations cause cathodic peaks on the chronoamperogram, while anions result in anodic peaks. For polyaniline with negatively charged substituents, a response to cations is observed, whereas the presence of uncharged ones results in anion detection. Moreover, in the case of the protonated –SO3H group, this compensating current is an order of magnitude lower than that for the deprotonated one. For electroactive self-doped polyanilines, the maximal amperometric signal is achieved at the working potential within the electroactivity range. The proposed constant potential amperometric approach was validated by the successful analysis of human serum with a Na+-selective electrode based on polyaniline.
{"title":"Amperometric Signal Generation by Self-Doped Polyanilines for Ion-Selective Electrodes","authors":"V. Shavokshina, A. Okoneshnikov, V. Nikitina, A. Karyakin","doi":"10.1134/s1061934824700126","DOIUrl":"https://doi.org/10.1134/s1061934824700126","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Flow injection amperometry provides an opportunity to avoid common drawbacks of classical potentiometry for solid-contact ion-selective electrodes. The current is generated by solid-contact in course of the polymer chain recharging in response to an excess of cations or anions in the polymer film. Cations cause cathodic peaks on the chronoamperogram, while anions result in anodic peaks. For polyaniline with negatively charged substituents, a response to cations is observed, whereas the presence of uncharged ones results in anion detection. Moreover, in the case of the protonated –SO<sub>3</sub>H group, this compensating current is an order of magnitude lower than that for the deprotonated one. For electroactive self-doped polyanilines, the maximal amperometric signal is achieved at the working potential within the electroactivity range. The proposed constant potential amperometric approach was validated by the successful analysis of human serum with a Na<sup>+</sup>-selective electrode based on polyaniline.</p>","PeriodicalId":606,"journal":{"name":"Journal of Analytical Chemistry","volume":"156 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141531982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-21DOI: 10.1134/s1061934824700163
Asmaa H. Abbas, Theia’a N. Al-Sabha, Subhi M. J. Al-Mtwaiti
Abstract
A spectrophotometric method has been developed for the determination of certain amine-phenol-containing drugs, namely, adrenaline, phenylephrine hydrochloride, and terbutaline sulfate. The method depends on the formation of new products by the reaction of drugs with the Gibbs reagent (2,6-dichloroquinone-4-chloroamide) in a basic borate buffer medium with a pH value of 11. The products were measured at 475, 652.5, and 547 nm for the aforementioned drugs, respectively. Beer–Lambert law was obeyed in the ranges of 0.3–9.5, 0.5–17, and 0.5–55 µg/mL with average recovery of 101.10, 99.13, and 99.78% and a relative standard deviation of ≤3.31%, respectively. The method was free from excipient interferences and applied successfully for the assay of the studied drugs in their pharmaceutical formulations. The resulting products were found in the ratio of 1 : 1.
{"title":"Spectrophotometric Determination of Adrenaline, Phenylephrine Hydrochloride, and Terbutaline Sulfate Using the Gibbs Reagent","authors":"Asmaa H. Abbas, Theia’a N. Al-Sabha, Subhi M. J. Al-Mtwaiti","doi":"10.1134/s1061934824700163","DOIUrl":"https://doi.org/10.1134/s1061934824700163","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>A spectrophotometric method has been developed for the determination of certain amine-phenol-containing drugs, namely, adrenaline, phenylephrine hydrochloride, and terbutaline sulfate. The method depends on the formation of new products by the reaction of drugs with the Gibbs reagent (2,6-dichloroquinone-4-chloroamide) in a basic borate buffer medium with a pH value of 11. The products were measured at 475, 652.5, and 547 nm for the aforementioned drugs, respectively. Beer–Lambert law was obeyed in the ranges of 0.3–9.5, 0.5–17, and 0.5–55 µg/mL with average recovery of 101.10, 99.13, and 99.78% and a relative standard deviation of ≤3.31%, respectively. The method was free from excipient interferences and applied successfully for the assay of the studied drugs in their pharmaceutical formulations. The resulting products were found in the ratio of 1 : 1.</p>","PeriodicalId":606,"journal":{"name":"Journal of Analytical Chemistry","volume":"49 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141531983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mycophenolic acid is a secondary metabolite of Penicillium brevicompactum and has been extensively studied for its antineoplastic, immunosuppressive, anti-inflammatory, antiviral, antipsoriasis, and antifungal activities. In the present study, a high-performance thin-layer chromatography method was developed for determining mycophenolic acid and a chitosan-linked prodrug using 60 F254 silica gel plates. The mobile phase used was chloroform–methanol–water (9.2 : 0.7 : 0.1, v/v/v), which provided good separation. The linearity was found to be in the range of 4–12 µg/spot with an R2 value of 0.9973. The percentage of RSD for intra-day and inter-day precision was found to be in the range of 0.7–1.1 and 0.9–2.0, respectively. The limit of detection and limit of quantification of the prodrug were determined to be 0.27 and 0.82 µg/spot, respectively. The recovery of the prodrug obtained was found to be 99.79%, suggesting that the method is simple, accurate, and reproducible. The proposed method proved to be sensitive, accurate, precise, economical, and less time-consuming, making it suitable for successful analysis in microsphere formulations.
{"title":"Determination of a Macromolecular Prodrug in Bulk and Microsphere Formulation by High Performance Thin Layer Chromatography","authors":"Sakshi Shinde, Tejaswani Shinde, Gajanan Shelke, Trupti Kachave, Shakuntala Chopade","doi":"10.1134/s1061934824700199","DOIUrl":"https://doi.org/10.1134/s1061934824700199","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Mycophenolic acid is a secondary metabolite of <i>Penicillium brevicompactum</i> and has been extensively studied for its antineoplastic, immunosuppressive, anti-inflammatory, antiviral, antipsoriasis, and antifungal activities. In the present study, a high-performance thin-layer chromatography method was developed for determining mycophenolic acid and a chitosan-linked prodrug using 60 F<sub>254</sub> silica gel plates. The mobile phase used was chloroform–methanol–water (9.2 : 0.7 : 0.1, v/v/v), which provided good separation. The linearity was found to be in the range of 4–12 µg/spot with an <i>R</i><sup>2</sup> value of 0.9973. The percentage of RSD for intra-day and inter-day precision was found to be in the range of 0.7–1.1 and 0.9–2.0, respectively. The limit of detection and limit of quantification of the prodrug were determined to be 0.27 and 0.82 µg/spot, respectively. The recovery of the prodrug obtained was found to be 99.79%, suggesting that the method is simple, accurate, and reproducible. The proposed method proved to be sensitive, accurate, precise, economical, and less time-consuming, making it suitable for successful analysis in microsphere formulations.</p>","PeriodicalId":606,"journal":{"name":"Journal of Analytical Chemistry","volume":"46 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141525835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-21DOI: 10.1134/s1061934824700023
E. A. Yuskina, V. V. Panchuk, D. O. Kirsanov
Abstract
The development of chemical sensor devices operating in non-contact mode is of primary interest due to the demand from various industries for a fast, simple and inexpensive determination of chemical composition in different media in a non-invasive way. One of the promising directions for the development of analytical devices with such characteristics is the use of high-frequency electrical signals. The paper discusses the evolution of high-frequency contactless conductometry method, likewise other methods and devices operating on similar physical principles (dielectric spectroscopy, microwave sensors, C4D detectors).
{"title":"Evolution of Contactless Conductometry Methods","authors":"E. A. Yuskina, V. V. Panchuk, D. O. Kirsanov","doi":"10.1134/s1061934824700023","DOIUrl":"https://doi.org/10.1134/s1061934824700023","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The development of chemical sensor devices operating in non-contact mode is of primary interest due to the demand from various industries for a fast, simple and inexpensive determination of chemical composition in different media in a non-invasive way. One of the promising directions for the development of analytical devices with such characteristics is the use of high-frequency electrical signals. The paper discusses the evolution of high-frequency contactless conductometry method, likewise other methods and devices operating on similar physical principles (dielectric spectroscopy, microwave sensors, C4D detectors).</p>","PeriodicalId":606,"journal":{"name":"Journal of Analytical Chemistry","volume":"18 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141529664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-21DOI: 10.1134/s1061934824700035
A. V. Erkovich, E. I. Korotkova, E. V. Dorozhko, A. N. Solomonenko, N. V. Aseeva
Abstract
The hydroxyl radical is the most aggressive and dangerous product of incomplete oxygen reduction in a body, making its determination and the effect of various antioxidants on the inhibition of OH radicals a pertinent task. We propose an impedance sensor for the determination of hydroxyl radicals, based on a graphite electrode modified with electrochemically deposited gold and a self-assembled monolayer of N-acetyl-L-cysteine (NAC). The use of NAC ensures the high selectivity of the sensor, and employing non-Faradaic impedance as a method of recording the analytical signal ensures the limit of detection for OH radicals at the level 0.01 nM with a linearity range of detectable concentrations from 0.08 to 8 nM. The developed sensor has been successfully used to assess the activity of certain antioxidants (ascorbic acid, glutathione, coenzyme Q10) towards OH radicals.
{"title":"An N-Acetyl-L-Cysteine Impedance Sensor for Assessing Antioxidant Activity against Hydroxyl Radicals","authors":"A. V. Erkovich, E. I. Korotkova, E. V. Dorozhko, A. N. Solomonenko, N. V. Aseeva","doi":"10.1134/s1061934824700035","DOIUrl":"https://doi.org/10.1134/s1061934824700035","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The hydroxyl radical is the most aggressive and dangerous product of incomplete oxygen reduction in a body, making its determination and the effect of various antioxidants on the inhibition of OH radicals a pertinent task. We propose an impedance sensor for the determination of hydroxyl radicals, based on a graphite electrode modified with electrochemically deposited gold and a self-assembled monolayer of <i>N</i>-acetyl-L-cysteine (NAC). The use of NAC ensures the high selectivity of the sensor, and employing non-Faradaic impedance as a method of recording the analytical signal ensures the limit of detection for OH radicals at the level 0.01 nM with a linearity range of detectable concentrations from 0.08 to 8 nM. The developed sensor has been successfully used to assess the activity of certain antioxidants (ascorbic acid, glutathione, coenzyme Q10) towards OH radicals.</p>","PeriodicalId":606,"journal":{"name":"Journal of Analytical Chemistry","volume":"33 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141529667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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