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Journal of Analytical Chemistry
Journal Prestige (SJR): 0.265  Citation Impact (citeScore): 1 Number of Followers: 20  Hybrid journal (It can contain Open Access articles)ISSN (Print) 1608-3199 - ISSN (Online) 1061-9348 Published by Springer-Verlag  [2468 journals]
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- Chromatographic Determination of Diflubenzuron Residues in Agricultural
Plant Matrices-
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Abstract: The article deals with the development of a method for the determination of diflubenzuron in agricultural products using HPLC with a diode array detector. The samples were extracted with acetonitrile, and then purified by solid-phase extraction using C18E and PSA adsorbents and a Diapak C cartridge. The developed method was tested on the green mass of plants, potato tubers, corn grain, soybeans, sunflower seeds, rapeseed, and vegetable oil in the concentration range from 0.025 to 0.25 mg/kg. The average values of recovery were 81–91% with an error of 1.3–2.3%.
PubDate: 2023-04-01
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- Quantification of Triacetin in a Mixture of Tri-, Di-, Monoacetin and
Glycerol by qHNMR Technique-
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Abstract: Glycerol derivative triacetin (TA) has diverse applications in the pharmaceutical, fuel, cosmetic, and food industries. Hence, it is vital to quantify triacetin in a given sample before it can be employed for a suitable commercial application. The conventional HPLC based method of TA quantification is time-consuming, leads to generating liquid waste, and requires unique columns, reference materials, and a suitable detector for the identification of molecules under investigation. To simplify TA quantification, herein, we have proposed a quantitative proton nuclear magnetic resonance (qHNMR) based method which does not require any complicated sample preparation method, sample derivatization, long analysis time, or highly pure reference materials. For TA quantification, an equation based on proton NMR analysis of standard mixtures of TA and glycerol of variable compositions is proposed. To validate the developed method, TA was quantified in samples with its variable concentrations by either qHNMR or HPLC, and the results were found to be comparable (R2 = 0.99). Further, to demonstrate the practical application, the technique was employed to quantify TA formed during acetylation of glycerol with acetic acid at various time intervals.
PubDate: 2023-04-01
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- Photolytic and Oxidative Degradation Behavior of Anticancer Drug
Venetoclax: Characterization of New Degradation Products Using High
Resolution Mass Spectrometry-
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Abstract: Venetoclax (VEN), an anticancer drug, was subjected to photolytic and oxidative degradation studies. The comprehensive degradation profiling of VEN in both conditions was reported. All the degradation products (DPs) were separated on reversed phase HPLC by employing an X-Bridge C18 column with ammonium acetate (pH adjusted to 3.20 with acetic acid) and organic solvent mixture of methanol with acetonitrile in the ratio of 90 : 10 as mobile phase. The overall results showed that it underwent significant degradation upon exposure to light (acidic pH) and oxidative (H2O2 at room temperature and 2,2-azobisisobutyronitrile at 40°C) conditions. A total of fifteen new DPs were identified with high resolution mass spectrometry data generated from liquid chromatography–high resolution mass spectrometry system. This information was used for the establishment of a complete degradation pathway of VEN. Additionally, in silico properties, viz., absorption, distribution, metabolism, excretion and toxicity (ADMET), of VEN and its DPs were predicted with admetSAR software.
PubDate: 2023-04-01
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- In situ Colorimetric Determination of Bisphenol A Using Silver
Nanoparticles-
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Abstract: Bisphenol A (BPA, 4,4'-dihydroxy-2,2-diphenylpropane) which has carcinogenic effects in breast and ovarian cancers can be released from cans and polycarbonate plastic products in dependence of temperature and pH. The present paper reports a simple spectrophotometric method for BPA detection in baby bottles and compact disks in the presence of Triton X-100. The proposed method is based on the formation of silver nanoparticles (AgNPs) in a medium containing ammonia and sodium hydroxide. The yellow color of AgNPs resulting from the localized surface plasmon resonance of AgNPs at 425 nm makes it possible to quantify BPA. Under the optimized conditions, the calibration curve of the proposed method was linear in the concentration range of 0.06–4 mg/L with the detection limit of 20 µg/L. The proposed method was successfully applied to determine BPA in some common products including baby bottles and compact disks after extraction in alkaline media.
PubDate: 2023-04-01
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- Analyte-Mediated Peroxidase-Mimicking Activity Enhancement of
Cysteine-Capped Silver Nanoparticles for Colorimetric Detection of Copper
Ions-
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Abstract: A novel and efficient colorimetric assay was developed for the detection of copper ions (Cu2+) in real environmental water based on analyte-mediated peroxidase-mimicking activity enhancement of cysteine-capped silver nanoparticles (RSH-AgNPs). These RSH-AgNPs show a synergetic effect in the form of peroxidase-mimicking activity enhancement by analyte mediation, and free RSH-AgNPs alone have weak catalytic properties. While coexisting with Cu2+, RSH-AgNPs possess excellent enzymatic activity due to the dissociation of cysteine on the interface of silver nanoparticles caused by Cu2+ and exposing the catalytic sites of AgNPs, which can catalyze the decomposition of hydrogen peroxide and trigger the oxidation of 3,3',5,5'-tetramethylbenzidine, leading to a change in color from colorless to blue. Using this strategy, Cu2+ could be determined within a wide linear range of concentrations (0.1 to 83 μM) with the detection limit of 0.08 μM using colorimetric detection. This method has excellent anti-interference capability and is effective and reliable for the determination of Cu2+ in real water samples.
PubDate: 2023-04-01
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- Quantification of Genotoxic Impurities by HPLC in Active Pharmaceutical
Ingredient Lorazepam-
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Abstract: A simple and selective reversed-phase high performance liquid chromatography method was developed and validated for the quantification of 4-chloroaniline, 2-chloro-N-(4-chloro-2-(2-chlorobenzoyl)phenyl)acetamide and 2-iodo-N-(4-chloro-2-(2-chlorobenzoyl)phenyl)acetamide in lorazepam. 4‑Chloroaniline is used as a raw material and 2-chloro-N-(4-chloro-2-(2-chlorobenzoyl)phenyl)acetamide and 2-iodo-N-(4-chloro-2-(2-chlorobenzoyl)phenyl)acetamide are formed as intermediates in the synthesis of anxiety disorder active pharmaceutical ingredient lorazepam. This method provided excellent sensitivity and a typical target analyte level of 150 ppm. This method was developed on an Agilent poroshell 120 EC-C18 (100 × 4.6 mm, 4 µm) column and a photo diode array detector. The proposed method is specific, linear, accurate and precise. The calibration curve was linear over the concentration range of LOQ to 120% with a correlation coefficient of 0.99. This method has low limits of detection and quantification for all the analytes. Accuracy was observed within the range of 85–115% for all the analytes. The developed method was validated as per the ICH guidelines in terms of specificity, precision, limit of detection, limit of quantification, linearity range and accuracy.
PubDate: 2023-04-01
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- Solid-Phase Extraction Assisted Dispersive Liquid–Liquid Microextraction
of Pyrene and Phenanthrene-
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Abstract: Zinc oxide nanoparticles-chitosan assisted dispersive liquid–liquid microextraction (DLLME) was utilized to microextraction of ultra-traces of pyrene and phenanthrene from seawater samples of Chabahar Bay prior to HPLC analysis with UV detection. The analytes dispersed into organic phase with the assistance of zinc oxide nanoparticles-chitosan in the modified DLLME method. The effect of factors on extraction efficiency, including amount of zinc oxide nanoparticles-chitosan, amount of chitosan, amount of zinc oxide nanoparticles, type and volume of extraction and dispersive solvents, extraction time and rate, and time of centrifugation, was optimized and investigated. Under optimized conditions, good linearity ranges of 1.0–150 µg/L for phenanthrene and 5–75 µg/L for pyrene were achieved. Based on standard deviation to slope of calibration curve ratio of 3, the limits of detection were 0.4 and 1.7 µg/L for phenanthrene and pyrene, respectively. Relative standard deviation was between 1.8–8.8%. The protocol was successfully utilized to the determination of pyrene and phenanthrene in seawater samples of Chabahar Bay. Relative recoveries from 79.0 to 105.0% were observed for the spiked seawater samples.
PubDate: 2023-04-01
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- In vitro Antioxidant and Cytotoxic Potential of Pleurotus Mushroom and
Activity-Based Correlation: a Comparative Study-
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Abstract: Herein, comparative studies were conducted on different species of Pleurotus mushroom (Pleurotus osteratus, Pleurotus eryngii, Pleurotus sajor caju, Pleurotus florida, and Pleurotus roseus), extracted in two different solvent systems: dichloromethane (DCM)–ethanol (Et) with the ratio of 1 : 1 (v/v) and 50% (v/v) ethanol. Comparably, 50% (v/v) ethanolic crude extract had a considerably higher extraction yield and total phenolic, carbohydrate, and protein content. Owing to a high total phenolic yield, 50% (v/v) ethanolic crude extract had better ability to scavenge 2,2-diphenyl-1-picryl-hydrazyl-hydrate and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid radical. Contrarily, DCM−Et crude extract showed strong cytotoxic potential against the human breast cancer cell line (MD-MBA-231) and murine skin cancer cell line (B16F10). High-performance thin layer chromatography based methods were developed and validated as per the International Council for Harmonisation Q2(R1) for the determination of ergosterol. Ergosterol content in DCM−Et crude extract correlates with its cytotoxic potential.
PubDate: 2023-04-01
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- Use of Magnetic Carbon Nanocomposites in the Formation of a Recognition
Layer of a Piezoelectric Immunosensor for the Determination of Penicillin
G-
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Abstract: Conditions for the formation of a recognition layer of a piezoelectric immunosensor based on magnetic carbon nanocomposites (MCNCs) under the action of an external magnetic field are studied. The effects of the size and number of magnetic nanoparticles (MNPs) in the composite on the analytical characteristics of the gravimetric immunosensor are revealed. Scanning electron microscopy is used to determine the average sizes of Fe3O4 magnetic nanoparticles synthesized by coprecipitation. It is noted that the minimum weight and stability of the recognition layer were observed for the nanocomposite obtained at a ratio of carbon nanotubes and MNPs with an average diameter of 22 nm equal to 3 : 1. The formation of peptide bonds between the MCNCs and a penicillin G conjugate was established by IR spectrometry. It was shown that the use of magnetic carbon nanocomposites in the formation of a recognition layer makes it possible to significantly simplify the procedure for preparing a piezoelectric sensor for analysis and reduce its duration from 24 to 1.5 h. The range of the determined antibiotic concentrations is 1–450 ng/mL, the limit of detection is 0.5 ng/mL.
PubDate: 2023-04-01
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- Using Smartphones in Chemical Analysis
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Abstract: The review covers the current status and prospects for the development of digital colorimetry using a smartphone as a color recording device. The applications of the rapid analysis methodology for the control of environmental samples, biological fluids, food products, drugs, and some specific samples are systematized. Various approaches are considered, ensuring the formation of an analytical signal in digital colorimetry. The capabilities (advantages and disadvantages) of a smartphone equipped with various software products make it a universal, mobile, rapid, and sensitive tool in the analysis of various samples.
PubDate: 2023-04-01
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- Chromatographic Assessment of the Concentration of Phenolic Compounds in
Wild Chamomile (Matricaria chamomilla L.) Extracts Obtained under Various
Extraction Conditions-
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Abstract: Results of a study of water and water–alcohol extracts of wild chamomile (Matricaria chamomilla L.) depending on the conditions of their extraction by different methods are discussed. The test samples are wild chamomile samples collected in various regions of Russia. Phenolic components in their native forms were extracted from medicinal raw materials using infusion, maceration, microwave-assisted, ultrasound-assisted, and subcritical extraction, and by the pharmacopoeial method. Concentrations of individual components and total phenolic compounds in wild chamomile were determined by chromatographic methods. The HPLC determination of phenolic compounds with diode-array and mass spectrometric detection was carried out using gradient elution with a mixture of acetonitrile with 0.1% formic acid. Chlorogenic acid, ferulic acid glycosides, luteolin-7-O-glucoside, dicaffeoylquinic and chicoric acid, apigenin-7-glucoside, and apigenin were identified in water and water–alcohol extracts of wild chamomile. The dependence of the concentration of phenolic compounds on the geographical place of the growth of plant raw materials was studied based on value of this parameter in extracts of wild chamomile samples from different territories. The maximum total concentration of phenolic compounds (10.1 mg/g) was found in the extract of chamomile from FarmaTsvet (Krasnogorsk, Moscow oblast).
PubDate: 2023-04-01
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- Modern Methods and Current Trends in the Analytical Chemistry of
Flavanones-
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Abstract: The review covers the specific features of the structure of flavanones and a critical review of methods for their determination in various samples. The data are summarizes according to the methods of analysis: chromatographic, electrophoretic, spectral, and electrochemical. Analytical possibilities of each group of methods and their advantages and disadvantages are discussed. Special attention is paid to the use of chemically modified electrodes based on carbon nanomaterials, 3D nanoporous metal structures, composites of metal oxides and sulfide nanoparticles or dyes with carbon nanomaterials, and also combinations of modifiers of various types in flavanone voltammetry.
PubDate: 2023-04-01
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- Determination of Methane Dissolved in Water Using Metal-Oxide Sensors
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Abstract: The method for the determination of dissolved methane in water using the system based on a tubular selective membrane permeable to volatile organic substances and impermeable to liquid water is proposed. Purified air is passed through the membrane tube immersed in water. The air inside the tube is saturated with methane dissolved in water, which diffuses through the tube wall. Methane concentration is measured in the air passing through the membrane tube using a semiconductor metal oxide sensor. The sensitivity threshold and the response time of the system are estimated.
PubDate: 2023-03-01
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- Evaluation of a Possibility of the Application of “Electronic Nose” to
Monitoring Deviations in the Functional Obesity of Children in Hospital
Conditions: Observations of Changes during Treatment-
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Abstract: This work is a continuation of a study on the use of chemical gas sensors and a portable “electronic nose” for diagnosing obesity and related pathologies in children in a hospital. Using a portable Bio-8 device, 330 volatile skin compound profiles were measured in the forearm region on an empty stomach in various states of children with various diseases during inpatient examinations and treatment in the endocrinology department. Monitoring changes in the profile of volatile skin compounds during the period of hospital stay in obese children made it possible to identify priority metabolic disorders in multiple pathological disorders and diagnoses by a characteristic set of chemical biomerkers of processes, reliably detected in skin secretions on the right forearm. Multiparametric data of the “electronic nose” were processed by principal component analysis to assess ranking of the results into the groups “Normal” and “Obesity with a risk of the development of type 2 diabetes mellitus (DM)”. Based on the highly informative parameters of the sensor array, changes in the chemical composition of the skin gas profile on the right forearm during the period of patients’ stay in the hospital and the effectiveness of standard approaches in each specific case were evaluated, and the personalization of treatment was thus increased. Simple calculated parameters and a method for assessing lipid and carbohydrate metabolism disorders based on the signals of eight sensors above the skin measured for 200 s without sampling were proposed. The sensitivity of the method for monitoring changes in the metabolome in a hospital is at least 80%. Specificity for lipid metabolism disorders is 100%; for type 1 diabetes, 100%; and for mixed pathologies varies from 70 to 85%.
PubDate: 2023-03-01
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- Analysis of Small-Mass Biological Samples by ICP MS Using Microwave Acid
Digestion of Several Samples in the Common Atmosphere of a Standard
Autoclave-
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Abstract: To expand the available tools for the analysis of samples of biological and plant origin of small mass (10–20 mg) using ICP MS, we developed a construction made of three compact teflon reaction minivessels (inserts) of an internal volume of 3 mL, placed in a standard autoclave (EasyPrep) of a volume of 100 cm3 of a MARS-5 microwave system (CEM). The acid digestion of samples in reaction minivessels requires no more than 1.5 mL of highly pure acids. The digestion of samples proceeds in the common gas atmosphere of a standard autoclave filled with a needed volume of acids of pure for analysis grade. The method was tested on reference materials of plants and biological sample. The results obtained are in agreement with the certified values. The developed method ensures the decrease of the detection limits and obtaining new data on the concentrations of B, Ga, Y, Nb, Tl, Bi, and a number of rare-earth elements in the reference materials.
PubDate: 2023-03-01
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- Determination of Viscosity Improvers and Detergent Additives in Synthetic
Motor Oils by Gel Permeation Chromatography-
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Abstract: We proposed a procedure for the simultaneous determination of viscosity improvers and detergent additives in synthetic oils by gel permeation chromatography, including the preliminary liquid extraction of polar additives, solid-phase extraction of polymer additives on silica modified with magnesium oxide from oil raffinate, and the subsequent determination of analytes. The procedure was used to determine viscosity improvers and detergent additives in fresh and used synthetic motor oils, to control the quality of oils at different stages of operation, and to monitor the degree of purification of oils during their regeneration. In-process monitoring of additive concentrations during the operation of automotive equipment enables the timely control of the dynamics of engine oil degradation throughout its use and proper recommendations for its replacement in the system. The procedure was tested in the analysis of fresh and used multigrade synthetic motor oils Shell Helix Ultra 5W-30 and TP MAX Total 10W-40 and fresh multigrade synthetic motor oil Shell Rimula R5M 10W-40.
PubDate: 2023-03-01
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- Development and Validation of a Bioanalytical Method for the
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Abstract: In this study, a simple, accurate, precise, and cost-effective method based on reversed-phase high-performance liquid chromatography with diode array detection for the quantification of aceclofenac in a small volume of human serum (100 µL) was developed and validated according to US-FDA guidelines. Acetanilide was used as an internal standard. The analyte and internal standard were spiked in human serum and extracted using a simple protein precipitation technique. The analysis was carried out on a reversed-phase C18 HPLC column (5 μm, 4.6 × 250 mm) using 0.1% formic acid and acetonitrile in a ratio of 40 : 60 (v/v) as the mobile phase with UV detection at 275 nm at a flow rate of 1.2 mL/min. The developed method was found to be sensitive, selective, and linear over the concentration range of 0.8–20 µg/mL with good precision (RSD ≤ 15%) and accuracy (relative error ≤15%). The limit of detection and lower limit of quantification were found to be 0.3 and 0.8 µg/mL, respectively.
PubDate: 2023-03-01
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- Determination of Trace Mercury in Water Samples by Cloud Point Extraction
Coupled with Atomic Fluorescence Spectrometry-
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Abstract: A simple, rapid and efficient sample preconcentration method of ultrasonic assisted cloud point extraction (CPE) coupled with atomic fluorescence spectrometry (AFS) was developed for the determination of trace mercury in water samples. In this method, Thio-Michler’s ketone was used as a chelating agent and Triton X-114 was used as a surfactant to enrich trace mercury in the surfactant phase. Before AFS analysis, tributyl phosphate was added as an antifoam. Under the optimal extraction conditions, such as pH, the amount of chelating agent and surfactant, the detection limit of the method is 0.003 μg/L, the relative standard deviation is 4.2–8.6% and standard recovery rate is 85–106%. The results show that ultrasonic assisted CPE-AFS can be applied to the determination of trace mercury in clean water samples, such as surface water and tap water, with lower detection limit, good accuracy and precision and can meet the requirements of higher sensitivity for sample analysis.
PubDate: 2023-03-01
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- Methods for the Determination of Arsenic in Metallurgical Materials
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Abstract: The review summarizes the results of publications on methods for determining arsenic in metallurgical materials from 2000 to 2022.
PubDate: 2023-03-01
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- Monitor Calibrator as an Alternative to Spectrofluorimeter: Determination
of Quinine in Beverages and Medicinal Preparations-
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Abstract: A possibility of using a monitor calibrator for the determination of luminescent compounds is shown on an example of quinine. The determination is based on the irradiation of a sample with broadband radiation in the visible and near UV spectral regions from a built-in source exciting phosphor molecules and the simultaneous registration of the radiation incident on the detector. Measurement conditions are selected. Quinine can be determined in the range of 60−750 µM, the limit of detection is 20 µM. The determination is not affected by common inorganic ions, as well as sweeteners and acidity regulators present in many beverages. The developed method of determination is applicable to the analysis of carbonated drinks and drugs. Compared to a traditional spectrofluorimeter, monitor calibrator is characterized by compactness, mobility, ability of detecting luminescence in cuvettes of various sizes and shapes, and lower cost.
PubDate: 2023-03-01
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