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AbstractThis study presents a new method for simultaneous determination of fenoterol, procaterol, clenbuterol, terbutaline and isoprenaline drugs using thin-layer chromatography assisted by image analysis (HPTLC-IA) combined with sensitive detection modes. Separation of the selected drugs was obtained using HPTLC Silica gel 60 F254 plates and mixture of isopropyl alcohol, ethyl acetate and ammonia (20:25:1.5 v/v/v) as mobile phase. UV detection mode combined with the use of 2,2-diphenyl-1-picrylhydrazyl (DPPH•) and 2,2'-azino-bis (3-ethylbenzothiazoline)-6-sulfonic acid (ABTS+•) radicals were applied for the first time for sensible detection of the separated drugs. Grey, green, red and blue scales respectively were selected for image analysis and accurate quantification of spot area. According to the obtained result, the use of DPPH• and ABTS+• reagents revealed a higher sensitivity in detection and accurate quantification of the analyzed drugs. Lower limit of detection (LOD = 0.07 ± 0.03 µg/spot; 0.09 ± 0.03 µg/spot and 0.10 ± 0.04 µg/spot) was obtained for fenoterol, procaterol and terbutaline using the ABTS+• radical and red scale selection for image processing. With the exception of isoprenaline, the proposed HPTLC-IA method showed a good separation of fenoterol, procaterol, clenbuterol and terbutaline drugs from other compounds in urine samples. Good recovery was obtained for these drugs in spiked urine samples. [ABSTRACT FROM AUTHOR]

INTRODUCTION. The determination of impurities is a key requirement for the quality assessment of medicines because impurities can significantly impact the quality and therapeutic effectiveness. Pharmacopoeias are the most important scientific and methodological guidelines for manufacturers developing medicinal product specifications and regulators assessing these specifications as part of registration dossiers. Therefore, it is essential to harmonise national and international approaches to impurities.AIM. This study aimed to analyse and summarise pharmacopoeial requirements for and methodological approaches to the control, evaluation, and identification of organic impurities in medicines.DISCUSSION. The authors compared requirements for the control of organic impurities in small-molecule medicines set forth in national and international pharmacopoeias and guidelines of the International Council for Harmonisation of Technical Requirements for Medicinal Products for Medical Use (ICH) and the Eurasian Economic Union (EAEU). This comparison highlighted the differences in current approaches that require further harmonisation of the existing regulatory documentation. Additionally, this study analysed the popularity, advantages, and disadvantages of different options for determining impurities in two-component combination products (i.e. identified and/or unidentified impurities in one or each of the active substances). The analysis demonstrated the need to control nitrosamines and genotoxic impurities and to use selective and highly sensitive chromatographic methods.CONCLUSIONS. When drafting pharmacopoeial monographs for medicinal products, experts should consider the general approach set forth in the EAEU pharmacopoeia and regulations and in the ICH Q3B guideline. This approach recommends that process-related impurities of active substances should not be controlled at the medicinal product level. Therefore, pharmacopoeial monographs for active substances should distinguish degradation products from process-related impurities. Impurities should be determined for each active substance to ensure the quality and safety of fixed combination medicinal products. Priorities for improving the methodological approach to the control of organic impurities include using reference standards for impurities and acknowledging the necessity of impurity quantification.

Introduction: Kefir beverage has beneficial microorganisms that have healthgiving properties; therefore, they have a good potential to be probiotic. This study evaluated the probiotic potential, technological, and safety characteristics of Enterococcus faecalis, Lactococcus lactis, and Pichia fermentans isolated from traditional kefir beverages. Method: First, isolates were evaluated in terms of resistance to acid, alkali, bile salts, trypsin, and pepsin of the gastrointestinal tract. The auto-aggregation and co-aggregation ability of isolates were measured using spectrophotometry. Antimicrobial activities were assayed against important food-borne pathogens using the agar well diffusion method. Moreover, gamma-aminobutyric acid (GABA) production was investigated by thin-layer chromatography (TLC). Result: Among the isolates, P. fermentans had an 85% total survival rate, but its amount reached below 6 log CFU/ml which is considered non-resistant, and it showed the highest auto-aggregation (74.67%). Moreover, only L. lactis showed antimicrobial activity and had the highest co-aggregation with E. coli PTCC 1338 (54.33%) and L. monocytogenes ATCC 7644 (78%). Finally, an evaluation of the technological and safety characteristics of the strains showed that the strains produced GABA and were safe. Discussion: Although the isolates were not resistant to the gastrointestinal tract, their supernatant contained valuable natural compounds, including antioxidants, GABA, and antimicrobials, which can be used to produce functional foods and medicines. In addition, other approaches, such as increasing the initial number of strains, using foods as carriers of isolates, and encapsulating the isolates, can effectively increase the survivability of isolates in the gastrointestinal tract. [ABSTRACT FROM AUTHOR]

The chromatographic behavior of the selected compounds was studied under conditions of hydrophilic interaction liquid chromatography (HILIC). The effect of mobile phase composition on the retention in different chromatographic systems was systematically examined using high‐performance thin‐layer chromatography. The sorbents of different polarity and adsorption characteristics were selected and mixtures of water and organic solvents of various compositions, from pure water to pure organic solvent were used as mobile phases. Increasing the amount of water in the mobile phase leads to a conversion of the separation mechanism, and the retention curves have a characteristic "U" shape. The conversion between the adsorption and partition mechanisms is most likely continuous and depends on the chemical nature of separated substances, the stationary phase as well as on organic component of the mobile phase. Silica gel can be considered the most suitable stationary phase for the systematic investigation of the chromatographic behavior of the test compounds, whereas acetonitrile was the most suitable solvent. The obtained results contribute to the understanding of the dominant separation mechanism, the type, and the intensity of the interactions between separated substances with both stationary and mobile phases. Besides, the lipophilicity parameters obtained under HILIC conditions were evaluated and correlated with the calculated values. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The relevance of this study lies in the lack of reliable information on the key aspects of the molecular mechanisms of fatty hepatosis, a common mammalian disease, and its dangerous complications, such as fibrosis, cirrhosis, and hepatocellular carcinoma. These circumstances substantially complicate the prompt diagnosis of this hepatopathology and reduce the effectiveness of treatment. The metabolism of the heme derivative bilirubin is unique and inherent in the liver, which undergoes transformation due to hepatocyte enzyme systems to form neutral compounds, such as glucurono-conjugates and sulphoconjugates, which undergoes changes and requires analysis in fatty hepatosis in animals. The aim of the study was to determine the characteristic changes in the content of unconjugated bilirubin and its sulphoconjugate, glucuronide, monoglucuronide, monoglucoside, and diglucuronide in the blood, bile, and liver of rats under the modelling of fatty hepatosis and the administration of rehabilitation therapy. For this, the thin-layer chromatography method was used. It was found that under tetracycline-induced fatty hepatosis in laboratory rats, the concentration of unconjugated bilirubin in the blood decreased by 39.3%, bilirubin glucuronide by 44.4%, and the total fraction of bilirubin monoglucuronide and monoglycoside by 78.9%. Oral administration of the milk phospholipid complex in the composition of the BAS "FLP-MD" to sick animals ensured the maintenance of these indicators at the control level. The content of bilirubin glucuronide and bilirubin diglucuronide decreased in the liver tissue of the treated rats. When these animals were administered a phospholipid-containing bioadditives, the level of unconjugated bilirubin in the liver tissue increased by 22.2%, but the content of its conjugated forms decreased. The content of all the studied bilirubin fractions decreased in the bile of sick rats during self-rehabilitation. The components of the BAS "FLP-MD" in fatty hepatosis in rats did not affect the reduction of unconjugated bilirubin in bile but eliminated the inhibitory effect of the modelled pathology on the content of all conjugated forms of bilirubin. The findings can be used as biochemical markers to monitor the pigment metabolism in the development of fatty hepatosis in mammals. [ABSTRACT FROM AUTHOR]

This study investigated the insecticidal efficacy of essential oils (EOs) extracted from Ageratum conyzoides, Hyptis suaveolens, and Ocimum basilicum against female Anopheles mosquitoes, aiming to explore their potential as alternatives to synthetic insecticides amidst rising resistance issues. EOs were obtained through steam distillation from freshly harvested plant aerial parts, and their chemical compositions were analyzed using gas chromatography-mass spectrometry. The results revealed significant variations in chemical profiles among the oils, with precocene I dominating in A. Conyzoides, eucalyptol in H. suaveolens, and estragole in O. basilicum. Thin layer chromatography analyses revealed various components with rf values ranging from 0.25 – 0.93. Mosquito bioassay demonstrated varying knockdown effects across the oils, with H. suavolens achieving 77.5% knockdown within six minutes of the observation period. None of the oils or their combinations reached susceptibility status (98–100% mortality), indicating prevalent resistance among the mosquito population in the study area. The combination of A. conyzoides and H. suavolens essential oil gave the highest percentage mortality (70%) at the least time (9 minutes), this is a suggestion of synergistic activity. Despite resistance challenges, this study highlights the promise of botanical insecticides in sustainable mosquito control and underscores the ongoing need for innovation and adaptation in vector management strategies.

The article discusses the peculiarities of forensic examination of nalbuphine hydrochloride, a prescription medicine that can be purchased without a prescription in many pharmacies. At present, in Ukraine, nalbuphine is not subject to subject-quantitative accounting in healthcare facilities and by pharmaceutical manufacturers, but in some countries it is included in the list of narcotic drugs. It is emphasised that nalbuphine hydrochloride is a synthetic opioid analgesic, which is chemically similar to morphine and phenanthrene. In terms of pharmacological action, it belongs to the group of opioid receptor agonists-antagonists (pentazocine, buprenorphine, butorphanol). The article provides a brief overview of the effectiveness of nalbuphine for pain relief in various cases, as well as examples of abuse of opioids in combination preparations and facts of non-medical use of nalbuphine. The effectiveness of opioids as painkillers is undeniable, but today, given the risk/benefit ratio, the expediency of their long-term use is questionable. There are more and more recommendations to avoid the use of opioids. Nalbuphine in combination with other psychotropic substances, medicines and in large doses is life-threatening, so it is proposed to further study and control it more deeply at the state level by amending the Resolution of the Cabinet of Ministers of Ukraine “On Approval of the List of Narcotic Drugs, Psychotropic Substances and Precursors” of 6 May 2000 No. 770, in particular, to classify nalbuphine as a narcotic drug. The article analyses the peculiarities of sampling and sample preparation, the main stages of chemical research of this potentially dangerous opioid using thin-layer chromatography, infrared spectroscopy, gas chromatography with a mass-selective detector. It is emphasised that the experimental data presented in the article will help in choosing the most appropriate methods and conditions for the study of nalbuphine, and will allow an objective assessment of the results of expert research.

Lipidomic analysis in diverse biological settings has be-come a frequent tool to increase our understanding of the processes of life. Cellular lipids play important roles not only as being the main components of cellular membranes, but also in the regulation of cell homeostasis as lipid signaling molecules. Yeast has been harnessed for biomedical research based on its good conservation of genetics and fundamental cell organisation principles and molecular path-ways. Further application in so-called humanised yeast models have been developed which take advantage of yeast as providing the ba-sics of a living cell with full control over heterologous expression. Here we present evidence that high-performance thin-layer chroma-tography (HPTLC) represents an effective alternative to replace cost intensive mass spectrometry-based lipidomic analyses. We provide statistical comparison of identical samples by both methods, which support the use of HPTLC for quantitative analysis of the main yeast lipid classes.

Introduction: In Ayurveda, Shodhana is a method for purification or detoxification of some herbal drugs, minerals, and metals. Shodhana helps to remove or reduce the toxic properties of herbal drugs and enhances their therapeutic efficacy. Semecarpus anacardium Linn seeds (SA seeds) commonly known as Bhallataka is an important medicinal herb in Ayurveda. As the raw drug causes toxicity, it has to undergoes the Shodhana process to neutralize its toxic properties. Methods: In the present work, we studied transformation in chemical profiling of Shoodhit and Ashodhit Bhallataka (SA L.f) using high-performance thin-layer chromatography (HPTLC) profiling, thin-layer chromatography profiling, proton nuclear magnetic resonance (1H-NMR) fingerprinting, physicochemical analysis, and estimation of total phenolic and total flavonoids. The SA after Shodhana or purification process showed lesser oil contents as compared to raw drugs. Results: The Shodhana process led to the significant reduction of toxic fatty acid or oil content and reduction in the toxic phenolic components in the processed drug of SA L.f. The HPTLC profiling and 1H-NMR fingerprinting showed remarkable changes in the chemical profiling between the Shodhit and Ashodhit samples. The total phenolic and flavonoid content was found to be higher in unprocessed SA seeds than in the purified SA seeds. Conclusion: The study helps in the identification of the transformation of SA L.f. seeds concerning various chemical and physical attributes. The method used in the traditional medicine systems efficiently detoxify the raw drug of SA seeds. These approaches can be used in quality control analysis to ensure the effectiveness of Shodhana process.

Ferula assa-foetida (Apiaceae), a naturally occurring medicinal plant found in the Ghardaia region of the Algerian Sahara, has garnered interest for its therapeutic potential. This study aims to partially characterize and assess the antidiabetic activity of water-soluble Polysaccharides isolated from F. assa-foetida gum-resin (PGFA). PGFA were obtained through extraction with distilled water at 80°C for 2 hours, followed by polysaccharide precipitation using three volumes of ethanol 96% and subsequent freeze-drying. The extraction yield thus obtained was 24.3%. The total carbohydrate content was 77% ± 0.22%, comprising 46.35% ± 0.015% neutral carbohydrates and 18.7 ± 0.045% uronic acids. Thin-Layer Chromatography (TLC) analysis of PGFA revealed the presence of galacturonic acid, glucuronic acid, arabinose, galactose, rhamnose and xylose. Evaluation of the antidiabetic activity, specifically Alpha (α)-D-glucosidase inhibitors demonstrated a significant inhibitory effect of PGFA (77.66%) at a concentration of 100 mg/ml-1. This inhibition was compared to acarbose, a positive control, which exhibited strong inhibitory activity (100%) at the same concentration. These findings support for the use of polysaccharides extract from Ferula assa-foetida in preventing diabetic complications. [ABSTRACT FROM AUTHOR]

Background: Many effective formulations are available in Ayurveda for various diseases. These formulations are lagging in standardization due to the absence of reference standards, whereas maintaining quality standards of given medicines is the need of an hour. Daruharidradi Ghanvati is one such combination of six herbal drugs containing Daruharidra, Meshshrungi, Vijaysar, Mamajjak, Jambubija, and Methikabij. Each drug is described in various Ayurvedic antidiabetic formulations. Aim: The present study was aimed at setting a standard pharmacognostical and pharmaceutical profile of Daruharidradi Ghanavati. Materials and Methods: The study included the preparation of Daruharidradi Ghanavati using raw drugs. Later, Daruharidradi Ghanavati was subjected to pharmacognostical, physiochemical, and thin-layer chromatography analysis as per standard protocols. Results: The final observations were recorded. Pharmacognostical findings matched with that of individual raw drugs with no major change in the microscopic structure of the raw drugs during the preparation of Ghanavati. Conclusion: The quality of Daruharidradi Ghanavati tablet can be tested by pharmacognostical, physiochemical screening for the observations of the present study. [ABSTRACT FROM AUTHOR]

The solubility of pigments is of significant importance for the successful coloring of various products in the food industry. In this work, the solubility of anthocyanins and chlorophylls was analyzed by thin-layer chromatography. Plant pigments were applied to filter paper and placed in mixtures of hydrophilic, ethanol, methanol, hydrophobic solvents, heptane, chloroform, and petroleum ether. In addition, solutions of different pH were used to examine how pH changes the color of the plant pigments. By adding small amounts of a strong acid (hydrochloric acid), a strong base (sodium hydroxide), weak acids (citric acid and acetic acid), and salts (sodium hydrogen carbonate and sodium hypochlorite) to the pigment extracts, a palette of various colors in the pigments was observed. Based on the solubility data and the results of the color change in the pigments, anthocyanins were successfully used as a food color in a food product with acidic pH, lemonade, and a food product with basic pH, cookies. [ABSTRACT FROM AUTHOR]

IntroductionKefir beverage has beneficial microorganisms that have health-giving properties; therefore, they have a good potential to be probiotic. This study evaluated the probiotic potential, technological, and safety characteristics of Enterococcus faecalis, Lactococcus lactis, and Pichia fermentans isolated from traditional kefir beverages.MethodFirst, isolates were evaluated in terms of resistance to acid, alkali, bile salts, trypsin, and pepsin of the gastrointestinal tract. The auto-aggregation and co-aggregation ability of isolates were measured using spectrophotometry. Antimicrobial activities were assayed against important food-borne pathogens using the agar well diffusion method. Moreover, gamma-aminobutyric acid (GABA) production was investigated by thin-layer chromatography (TLC).ResultAmong the isolates, P. fermentans had an 85% total survival rate, but its amount reached below 6 log CFU/ml which is considered non-resistant, and it showed the highest auto-aggregation (74.67%). Moreover, only L. lactis showed antimicrobial activity and had the highest co-aggregation with E. coli PTCC 1338 (54.33%) and L. monocytogenes ATCC 7644 (78%). Finally, an evaluation of the technological and safety characteristics of the strains showed that the strains produced GABA and were safe.DiscussionAlthough the isolates were not resistant to the gastrointestinal tract, their supernatant contained valuable natural compounds, including antioxidants, GABA, and antimicrobials, which can be used to produce functional foods and medicines. In addition, other approaches, such as increasing the initial number of strains, using foods as carriers of isolates, and encapsulating the isolates, can effectively increase the survivability of isolates in the gastrointestinal tract.

Turmeric has traditionally been employed as a potent anti-inflammatory agent in Indian medicinal practices. Turmeric has historically been referred to as "Indian saffron" due to its vibrant yellow-orange hue and it has been utilised as a seasoning, medicinal treatment, and fabric dye. Turmeric contains a high concentration of curcuminoids, which have diverse chemical structures and physico-chemical properties. Distinctive attributes or qualities. This study presents a method for extracting curcuminoids utilizing a Soxhlet extractor machine. The process of purifying and measuring the amount of curcuminoids was conducted using thin layer chromatography. The maximal resulting extract was obtained by the process of TLC using Hexane as the solvent. The Soxhlet extraction procedure yielded a curcumin percentage of 4.09%. Various solvents were employed for the extraction process, and it was found that acetone exhibited the highest yield of each curcuminoid. The separation of curcuminoids was examined using thin-layer chromatography (TLC) with a chloroform: methanol solvent mixture at a ratio of 95:5. The resulting RF values for curcumin, di-methoxy-curcumin and bis de-methoxy-curcumin were 0.59, 0.61 and 0.58, respectively. [ABSTRACT FROM AUTHOR]

To establish a reliable method for measuring the radiochemical purity of technetium[99mTc] methylenediphosphonate injection, analysis conditions such as stationary phase and developing solvent were studied. The analytical method was methodologically verified in accordance with the Chinese Pharmacopoeia and other relevant provisions. The results showed that the analytical method of single-system thin-layer chromatography, in which polyamide-6 thin-layer plate was used as the stationary phase, V (1 mol/L sodium acetate solution): V (0.1 mol/L hydrochloric acid solution) =1∶1 mixed solution was used as the developing solvent, could improve the tailing problem of the main peak of technetium[99mTc] methylenediphosphonate injection. The resolution of radioactive main peak and potential impurities including pertechnetate[99mTc] and colloidal technetium[99mTc] was greater than 1.0. The method had a good linear relationship in the radioactivity range of 2.7×10-2 μCi to 42.4 μCi, and the correlation coefficient r was 0.997, with good specificity, good durability and intermediate precision. Compared with the analytical method of the pharmacopoeias, the relative error of radiochemical purity met the requirement of less than 2.0%. The established thin-layer chromatography is suitable for determination of the radiochemical purity of technetium[99mTc] methylenediphosphonate injection.

Scientific relevance. Cardiac glycosides have been used in medicine for over two centuries. Current studies suggest that biologically active substances from this group can be used to treat not only heart conditions but also viral infections, cancers, and other diseases. Therefore, quality control methods for cardiac glycosides are becoming increasingly relevant.Aim. Based on a review of Russian and international quality standards, as well as up-to-date scientific data, this study aimed to identify promising methods for the identification and quantification of cardiac glycosides in herbal drugs and herbal medicinal products, as well as to evaluate the possibility of substituting physicochemical methods for biological methods.Discussion. The methods that are currently used to standardise cardiac glycosides are either not selective or require laboratory animals (biological test systems). According to a study of pharmacopoeial methods for the identification of cardiac glycosides in herbal drugs and herbal medicinal products, chemical identification tests and thin-layer chromatography continue to be relevant. Quantitative testing of herbal drugs and extracts uses biological and non-selective (spectrophotometry) methods, whereas chromatography is described only in general and individual monographs for herbal drug preparations containing individual cardiac glycosides and medicinal products containing these preparations. Upon analysing quality standards and scientific publications, the authors identified potentially promising methods for the quantification of cardiac glycosides in herbal drugs, herbal drug preparations, and herbal medicinal products, namely chromatographic methods.Conclusions. Reverse-phase high-performance liquid cjromatography (HPLC) with spectrophotometric detection is the most suitable method for pharmacopoeial analysis. The development of an HPLC-based analytical procedure to determine the cardiac glycoside content will provide an opportunity to advance from biological or non-selective methods to more ethical and selective up-to-date techniques.

Predicting the biological properties of newly synthesized compounds plays a key role in the process of synthesis of new compounds and their evaluation as potential drug candidates. The large number of methods and models available often makes it confusing to choose a suitable one in the context of given investigated compounds. In this paper, a comparison of data obtained using 46 in silico models predicting various properties and retention parameters of compounds on the basis of data obtained in 8 commonly available thin-layer chromatographic (TLC) systems for 14 commercially available drugs was carried out using the principal component analysis (PCA) method. The results obtained show similarities between the RM0, S, and φ0 values calculated for the investigated TLC systems and the sets of descriptors obtained from the in silico calculations, enabling an evaluation of the interchangeability of the investigated methods. [ABSTRACT FROM AUTHOR]

Reversed-phase chromatography is based on a polar mobile phase and an apolar stationary phase. This separation mode is regularly used in planar (thin-layer) chromatography, and the necessary plates are commercially available. We investigated the preparation of hydrophobic plates for thin-layer chromatography by chemical vapor sorption of methyltrimethoxysilane directly onto a normal-phase plate. For this, a commercial normal-phase plate is simply exposed to the vapors of the reagent in a closed vessel. The obtained plates were characterized by infrared spectroscopy and dynamic water vapor sorption, which reported an extensive conversion of free hydroxyl groups by the reagent. The obtained plates were hydrophobic with a water contact angle close to 135°. The extent of hydrophobization precluded the use of pure water as an eluent while mixtures with organic solvents were perfectly adequate. The plates' chromatographic performance was compared with that of C18 and paraffin-coated plates. For this, a set of parabens was separated with mixtures of acetone and water. The height of a theoretical plate was similar for the hydrophobized and the C18 plates (50–90 µm) and larger for the paraffin-coated ones. In contrast to the C18 plate, the hydrophobized and the paraffin-coated plates showed some selectivity for the analyte pair n-butylparaben and iso-butylparaben, which indicates a separation mechanism with the potential for regioselectivity. [ABSTRACT FROM AUTHOR]

This study presents the establishment of surface-enhanced Raman spectroscopy (SERS) combined with the thin-layer chromatography (TLC) method for detecting four types of quinolone antibiotics in aquatic products. The experimental procedure involved ultrasonic extraction using methanol as the extraction solvent to isolate the target ingredients. The quinolone antibiotics were separated using chromatography conditions with Merck silica gel G TLC plate as a stationary phase and a chloroform – methanol – ethyl acetate – ammonia solution (5 : 12 : 1 : 4) as a mobile phase. Silver sol was used as the matrix to obtain SERS peaks for quinolone. The quinolone antibiotics were identified using SERS in aquatic products. Subsequently, normal SERS spectra of quinolone antibiotic powder, quinolone antibiotic preparations, SERS characteristic peaks, and quinolone antibiotic in fish and shrimp were analyzed. The TLC chromatography system allowed to achieve the separation of four quinolone preparations. The system suitability test showed that the humidity range was 18–88%, and the durability range was between 20–50°C. Moreover, the established TLC-SERS method successfully identified quinolones in aquatic products. Therefore, the SERS method could achieve the effective qualitative determination of quinolones, offering high sensitivity, simple operation, and high timeliness, and is suitable for the rapid detection of quinolones. [ABSTRACT FROM AUTHOR]

The combination of trimethoprim and sulfamethoxazole as a fixed-dose combination in the ratio 1:5 is known as cotrimoxazole. It is used as antibiotic to treat a variety of bacterial infections. Cotrimoxazole is part of the World Health Organization's list of essential medicines. Cotrimoxazole is an example of a drug that was partially unavailable in Germany during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic and the Ukraine war. The dependency on foreign sources of medicines is well known in Europe and resulted in the Pharmaceutical Strategy for Europe 2020, a strategy concept "will support the competitiveness and innovative capacity of the EU's pharmaceutical industry". High-performance thin-layer chromatography (HPTLC) is a cost-effective method for quantifying pharmaceutically active compounds. Diode-array detection (DAD) in conjunction with HPTLC can simultaneously detect ultraviolet‒visible (UV‒VIS) and fluorescence spectra directly from the plate. Visualization as a contour plot helps to identify the optimal wavelengths for compound quantification and reduce uncertainty in the determination. The quantification of trimethoprim and sulfamethoxazole is presented in a case study that highlights the key aspects for HPTLC quantification of pharmaceutical fixed-dose combinations with minimal uncertainty. HPTLC‒DAD allows quantification of trimethoprim and sulfamethoxazole with a required relative standard deviation of less than 2.5%. [ABSTRACT FROM AUTHOR]

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A novel economic thin layer chromatographic method for stereoselective separation of racemic mixture of (RS)-Indapamide and determination of their enantiomers was done. The method was based on using normal TLC plates and cyclodextrin with hydroxylic part, was used as the chiral selector. Cyclodextrin was used as an additive in silica gel to prepare a TLC plate which was a non-covalent bonding, and there was no chiral substance added in the solvent system. The mobile phase was toluene-ethyl acetate-MeOH-glacial AcOH (6:4:1:0.1). Cyclodextrin was also added to mobile phase, and there was no chiral selector in the stationary phase. The mobile phase was a mixture of toluene-ethyl acetate-MeOH-glacial AcOH-5mM CD (6:4:1:0.1:1.0). The spots were then isolated and identified. The impact of the components of mobile phase, temperature, and pH was studied for the finding the best separation conditions. The spots were sited in a chamber which had Iodine granules. [ABSTRACT FROM AUTHOR]

A first integrative survey of the genus Usnea in the southern Philippines, taking into account morphological, anatomical, chemical and molecular characters, resulted in the recognition of 20 taxa, including three species new to science: Usnea angulata Ach., U. baileyi (Stirt.) Zahlbr., U. bismolliuscula Zahlbr., U. brasiliensis (Zahlbr.) Motyka, U. confusa Asah., U. croceorubescens Stirt., U. dasaea Stirt., U. himalayana C. Bab., U. krogiana P. Clerc, U. longissima Ach., U. nidifica Taylor, U. norsticornuta A. Gerlach & P. Clerc sp. nov. (characterized by a moderately thick cortex and by the presence of norstictic acid), U. paleograndisora A. Gerlach & P. Clerc sp. nov. (characterized by an orange subcortical pigmentation in the medulla, with enlarging soralia and a moderately thick and shiny cortex), U. pectinata Taylor, U. pygmoidea (Asahina) Y. Ohmura, U. rubicunda Stirt., U. rubrotincta (Stirt.) Zahlbr., U. spinulifera (Vain.) Motyka, U. subscabrosa Motyka and U. yoshihitoi P. Clerc & A. Gerlach sp. nov. (characterized by a lax medulla with non-conglutinated hyphae). Usnea krogiana is a new record for Asia; Usnea brasiliensis , Usnea confusa and U. croceorubescens are new records for the Philippines. This is the first phylogenetic study to include DNA sequences of Usnea from the Philippines. Molecular data from the ITS rDNA (76 newly generated sequences) are presented for most taxa except for U. himalayana , U. longissima and U. subscabrosa. At least six further taxa remain unidentified, awaiting the collection of additional specimens. [ABSTRACT FROM AUTHOR]

A new, simple, rapid, low-cost, and robust thin layer chromatography-smartphone method has been developed for the qualitative and quantitative determination of carbamazepine in human plasma. Liquid–liquid extraction (LLE) with dichloromethane was used for sample purification. The drug of interest was separated on TLC aluminum coated with silica gel; and a mixture of cyclohexane, chloroform, and acetic acid (4:4:2 v/v/v) was used as the mobile phase. The sample spot was visualized under a UV chamber at 254 nm then photographed by a smartphone. The intensity of each spot was quantified by videodensitometry. The method was validated according to the guideline of the ICH Q2 (R1). The results showed good linearity (R > 0.99), high sensitivity, and reliable robustness. For accuracy and precision, acceptable relative standard deviations (RSD) were reached (<15%). The limits of detection and quantification were 0.94 µg/mL and 2.8 µg/mL, respectively. The comparison to HPLC method didn't show a significative difference (p =.314). The analysis of carbamazepine in samples charged with several interferences showed good recovery (>90%), except for phenobarbital (recovery = 72%). It was concluded that the proposed TLC-smartphone is a viable method that can be used for the analysis of carbamazepine in human plasma. [ABSTRACT FROM AUTHOR]

Ibuprofen is a pharmaceutical that is commonly used to reduce inflammation and to treat headaches. A thin-layer chromatographic method combined with simple and inexpensive digital imaging is proposed for the determination and quantification of ibuprofen. The recommendations of the standard pharmacopoeia were followed with the addition of a minimal spotting method as a local calibration curve (n = 3) and comparison with a spotted sample. Images were acquired using a smartphone and then converted to greyscale using Fiji, an open-source image analysis software. The peak area and density of each spot was then calculated using a densitometric principle. To analyse the present image data, several images were taken with different filters. Using a calibration curve ranging in the range of 3 to 5 mg/mL, linearity could be determined across the subjected images (R2 ranging from 0.984 to 0.996), with a mean accuracy of 99.9 ± 2.20% and RSD of 2.20%. The method studied, using smartphone imaging and open-source software (Fiji), offered a simple and inexpensive application for the quantification of ibuprofen in pharmaceuticals, applicable to preliminary studies and curricula. Method proposal for ibuprofen quantification using digital image processing software (Fiji) [ABSTRACT FROM AUTHOR]

Paracetamol is the most widely used analgesic drug in the world. However, the risk and the severity of poisoning with this medication are often underestimated. A simple and cost-effective method for screening paracetamol poisoning by using thin-layer chromatography (TLC) and a smartphone has been developed. Successful liquid‒liquid extraction of the drug from plasma was carried out. Then, samples were spotted on a TLC plate and eluted by a mobile phase of acetone‒hexane‒ammonia (4:5:0.1, V/V). JustTLC software was used to analyze and quantify paracetamol spots. The results of the analytical validation showed that our method is linear in the range of 80–180 µg/mL with a correlation coefficient of R2 > 0.99. The precision, the accuracy, and the robustness of the method were also verified. The limits of detection and quantification were 8.79 and 26.65 µg/mL, respectively. The comparison with an enzyme immunoassay and high-performance liquid chromatography (HPLC) method was satisfactory. This methodology opens up new promising perspectives in toxicology laboratories. [ABSTRACT FROM AUTHOR]

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The rising discharge of anthropogenic chemicals into aquatic environments poses a significant threat, necessitating effective monitoring strategies. This study introduces an innovative approach to effect-directed analysis (EDA) by coupling liquid chromatography (LC) with high-performance thin-layer chromatography (HPTLC), utilizing a modified MALDI spotter. The objective is to optimize fractionation parameters for sample application and assess the method's viability in identifying acetylcholinesterase (AChE) inhibitors, specifically malathion, parathion, and chlorfenvinphos.The optimization process involves controlling sample volume, spot shape, and spot distances on HPTLC plates. Successful application is demonstrated by a miniaturized LC system coupled to the HPTLC plate via spotter, allowing effective separation and identification of AChE inhibitors. The study further explores the method's application to water samples from a river with predominantly agricultural drainage area.Spiked samples reveal distinct active spots, identified through extraction and subsequent high-resolution mass spectrometry (HRMS) measurements. However, results indicate the absence of AChE inhibitors in non-spiked water samples, affirming the efficacy of the EU ban on most organophosphate pesticides. The usefulness of HPTLC in separation of coeluting substances from HPLC is emphasized, demonstrating its suitability for the effect-directed analysis of complex samples.This work shows the integration of HPTLC with liquid chromatography for EDA, offering a powerful tool for identifying and monitoring AChE inhibitors in water samples. The approach addresses limitations in current monitoring strategies and provides insights into the presence and impact of chemicals in aquatic ecosystems. The study contributes to ongoing efforts to enhance water quality monitoring, aligning with the principles of the EU Water Framework Directive.

Before formulating radiopharmaceuticals for injection, it is necessary to remove various impurities via purification. Conventional synthesis methods involve relatively large quantities of reagents, requiring high-resolution and high-capacity chromatographic methods (e.g., semi-preparative radio-HPLC) to ensure adequate purity of the radiopharmaceutical. Due to the use of organic solvents during purification, additional processing is needed to reformulate the radiopharmaceutical into an injectable buffer. Recent developments in microscale radiosynthesis have made it possible to synthesize radiopharmaceuticals with vastly reduced reagent masses, minimizing impurities. This enables purification with lower-capacity methods, such as analytical HPLC, with a reduction of purification time and volume (that shortens downstream re-formulation). Still, the need for a bulky and expensive HPLC system undermines many of the advantages of microfluidics. This study demonstrates the feasibility of using radio-TLC for the purification of radiopharmaceuticals. This technique combines high-performance (high-resolution, high-speed separation) with the advantages of a compact and low-cost setup. A further advantage is that no downstream re-formulation step is needed. Production and purification of clinical scale batches of [18F]PBR-06 and [18F]Fallypride are demonstrated with high yield, purity, and specific activity. Automating this radio-TLC method could provide an attractive solution for the purification step in microscale radiochemistry systems.

Scientific relevance. The State Pharmacopoeia of the Russian Federation, edition XIV, requires the identification of aniseed and fennel fruits by the same thin-layer chromatography (TLC) procedure using Sudan III and menthol. These markers are neither specific nor related to the therapeutic effects of these herbal drug products. The visual interpretation of chromatograms is complicated because of the low intensity of adsorption zones. Moreover, the corresponding compendial monographs do not characterise the adsorption zones specific to each of the plants. The most abundant component in aniseed and fennel essential oils, trans-anethole, would make a better reference standard from a methodological point of view.Aim. This study aimed to optimise the TLC procedure for essential oil determination in herbal drugs and herbal medicinal products of aniseed and fennel fruits and subsequently recommend it for inclusion in the relevant compendial monographs.Materials and methods. The study examined samples from several batches of herbal drugs, including aniseed and common fennel fruits, sourced from Russian manufacturers. The reference standards comprised commercial reagents, including trans-anethole, anise oil, and linalool, as well as fresh essential oils that had been steam distilled from the test samples in a Clevenger apparatus. The study was conducted by TLC. Sample preparation involved using Merck aluminium TLC plates, an IKA KS-501 digital orbital shaker, and a CAMAG Linomat 5 semi-automatic sample application system. The authors heated the plates in either a Binder ED53 drying oven or a CAMAG TLC plate heater. For visualisation, the authors selected a CAMAG TLC VISUALIZER 2 UV imaging and documentation system.Results. The informational and experimental research showed the feasibility of using trans-anethole as an identification reference standard for common anise and fennel fruits. The authors selected the optimal solvent for extracting active substances from the test products (hexane) and a detection reagent for improving visual evaluation of the chromatograms (1% sulfovanillin). The authors established characteristic adsorption zones for differentiating between aniseed and fennel fruits.Conclusions. The optimised procedure identifies the main components in the essential oils of aniseed and fennel fruits with a specific reference standard. This procedure may be recommended for inclusion in draft monographs for the corresponding herbal medicinal products.

Scientific relevance. When harmonising conditions for qualitative and quantitative analysis of bioactive compounds in herbal medicines, the Institute of Pharmacopoeia and Medicinal Product Standardisation has discovered that horse-chestnut products lack national quality standards.Aim. This study aimed to review international quality standards in order to identify the most promising testing methods for the main groups of bioactive compounds in horse-chestnut seeds and draw upon these methods when drafting national pharmacopoeial monographs for horse-chestnut seed products.Discussion. The authors compared the requirements established by leading world pharmacopoeias for the identification and assay of herbal drugs and herbal drug preparations derived from horse-chestnut seeds.Conclusions. The study results show that, predominantly, identification tests are based on thin-layer chromatography, assays rely on spectrophotometry, and aescin is used as a pharmacopoeial reference standard. The authors drafted a pharmacopoeial monograph for the medicinal product Horse-Chestnut Seed Dry Extract + Thiamine Hydrochloride, Oral Solution, which requires using thin-layer chromatography and spectrophotometry for qualitative and quantitative testing.

To date, the aetiology and molecular mechanisms of the development of fatty hepatosis, which is quite common in mammals, have not yet been sufficiently explained. This pathology requires detailed study not only because of functional disorders of the liver and biliary system, but also because of the high probability of dangerous complications – fibrosis, cirrhosis, or hepatocellular carcinoma. The purpose of this study was to determine marker changes in the phospholipid composition of bile and blood in rats with experimental fatty hepatosis and with the use of corrective therapy. Hepatopathology was modelled in Wistar laboratory rats by intragastric administration of a 4% solution of tetracycline hydrochloride at the rate of 0.25 g/kg body weight for seven days. Using the method of thin-layer chromatography, the phospholipid components of animal bile and blood were studied. It was found that during experimental fatty hepatosis in rats, there was a decrease in the total phospholipid content in bile, mainly due to a decrease in the level of phosphatidylcholine (by 22.4-27.0%), the total fraction of inositol phosphatide and phosphatidylinositol (by 20.0-27.3%), and phosphatidylethanolamine (by 17.5-25.2%). Conversely, the introduction of milk phospholipids in the form of a dietary supplement “FLP-MD” in sick animals contributed to an increase in bile levels of phosphatidylserine by 67.1-99.8%, inositol phosphatide and phosphatidylinositol by 48.6-57.6%, phosphatidylcholine by 38.8-60.2%, phosphatidylethanolamine by 45.6-57.4%, and sphingomyelin by 30.4-46.3%. In the blood of such rats, a significant decrease in the content of phosphatidylcholine, phosphatidylserine, and sphingomyelin was found, which was not observed after administration of the “FLP-MD” dietary supplement to sick animals. In the case of using the supplement in healthy animals, only a 29.3% increase in the blood content of inositol phosphatide and phosphatidylinositol was noted. The determination of the most sensitive indicators in the phospholipid spectrum of blood and bile reveals the features of changes in molecular processes for the development of fatty hepatosis in animals, and also contributes to preclinical tests of the corrective effectiveness of newly created drugs according to established markers

Background and Aim: Antibiotic residues in livestock farming have been identified as a potential cause of antimicrobial resistance in humans and animals. This study aimed to determine whether antibiotic residues were present in the chicken meat, eggs, feces, and feed collected from all four districts in the Mymensingh division of Bangladesh. Materials and Methods: To detect antibiotic residues in the collected samples, qualitative thin-layer chromatography (TLC) and quantitative high-performance liquid chromatography (HPLC) were used. A total of 230 samples were analyzed for commonly used 11 antibiotics residue. Out of these, 40 meats and 40 feces samples were collected from broilers and layers, 30 egg samples from duck and layer, and 120 feed samples from both broilers and layers from the study area. Thin-layer chromatography was used for screening the presence of antibiotic residues; TLC-positive samples were then subjected to further HPLC analysis to determine the residue concentrations. Results: Thin-layer chromatography analysis revealed that 23.5% of the tested samples contained residues from six different antibiotic classes (tetracyclines, quinolones, beta-lactams, sulfonamides, aminoglycosides, and macrolides). Thin-layer chromatography analysis showed that 35% and 25% of the meat samples were positive for residues from the broiler and layer, respectively. About 15% and 30% of layer and duck egg samples had positive residues, respectively. Out of 120 feed samples analyzed, about 15.8% had various antibiotic residues. In addition, feces samples from broilers and layers had 50% and 35% antibiotic residues, respectively. A total of 2.5% meat and 3.3% egg samples had antibiotic residues above the maximum residue limit (MRL). Based on the findings of this study, the highest percentage of oxytetracycline, followed by doxycycline and ciprofloxacin, were detected in feed samples, and oxytetracycline was detected in meat and egg samples. Conclusion: This study clearly showed the misuse of antibiotics in the poultry sector in Bangladesh. Although antibiotic residues below the MRL level are suitable for human consumption, they may result in antimicrobial drug resistance to pathogens.

Oaks (Quercus L., Fagaceae) are a widespread tree species worldwide, and in Hungary they account for nearly 30 % of the forests. Their wood is valuable, but their bark is considered as a by-product. Oak bark, available in large quantities but with no dedicated use, contains a significant amount of valuable extractives. Its (+)-catechin content is around 1 %. (+)-Catechin is mostly used for food industry, medicine and many other industrial purposes, representing a significant financial value. The aim of the present research was to compare the (+)-catechin concentrations in the bark of the most important oak species found in Hungary and to optimize sample pretreatment (conservation) and extraction methods in order to achieve fast and efficient extraction. From these species the highest concentrations were measured in Q. robur and Q. robur ssp. slavonica (8–12 mg (+)-catechin/g dry bark). The combination of microwave sample pretreatment and microwave assisted extraction proved to be the most time- and cost-effective method. The utilization of the extracted bark powder for energetic purposes requires further investigations.

High‐performance thin‐layer chromatography has favorable properties for high‐throughput separations with a high matrix tolerance. Sample preparation, however, is sometimes required to control specific matrix interferences and to enhance the detectability of target compounds. Trends in contemporary applications have shifted from absorbance and fluorescence detection to methods employing bioassays and mass spectrometry. Traditional methods (shake‐flask, heat at reflux, Soxhlet, and hydrodistillation) are being challenged by automated instrumental approaches (ultrasound‐assisted and microwave‐assisted solvent extraction, pressurized liquid extraction, and supercritical fluid extraction) and the quick, easy cheap, efficient, rugged, and safe extraction method for faster and streamlined sample processing. Liquid‐liquid extraction remains the most widely used approach for sample clean‐up with increasing competition from solid‐phase extraction. On‐layer sample, clean‐up by planar solid‐phase extraction is increasingly used for complex samples and in combination with heart‐cut multimodal systems. The automated spray‐on sample applicator, the elution head interface, biological detection of target and non‐target compounds, and straightforward mass spectrometric detection are highlighted as the main factors directing current interest toward faster and simpler sample workflows, analysis of more complex samples, and the determination of minor contaminants requiring high concentration factors. [ABSTRACT FROM AUTHOR]

In recent years, the interest in natural remedies has increased, so it is important to analyze the plants widely distributed in nature but whose composition is little known. The main objective of the present work is to obtain information based on the profiles of secondary metabolites and antioxidant activity in Lamium album, a very widespread but little studied plant, with the aim of revealing the differences compared to Urtica dioica. First, the optimization of enzymatic extraction assisted by ultrasound was carried out by the Box–Behnken method. The optimized parameters were: concentration of the enzyme—3.3% cellulase, temperature—55 °C, and the extraction time—40.00 min. The efficiency was estimated based on the content of iridoids, the main class of secondary metabolites from Lamium album. Second, the secondary metabolites profiles of the nettle extracts were obtained by thin-layer chromatography using both normal and reverse phases and by RP-UHPLC. The antioxidant activity was evaluated using DPPH and ABTS+ radicals. The obtained results revealed significant differences between the two nettle species, both in terms of the phytochemical compounds, as well as the antioxidant activity, confirming the fact that Lamium album has a high potential to be used in phytomedicine. [ABSTRACT FROM AUTHOR]

Black cumin herb (Nigella sativa L.) was identified and standardized by analyzing the chemical composition and developing methods for determination of the authenticity and flavonoid content as biologically active compounds. Three flavonoids, nicotiflorin (kaempferol 3-O-β-D-glucopyranoside), rutin, and nigelflavonoside G {3-O-β-D-[_-L-O-rhamnopyranosyl-(1→6)]-glucopyranoside-[(2→1)-O-β-D-glucopy- ranosyl-(2→1)-O-β-D-glucopyranosyl]-3,5,6,7,4′-pentahydroxy-3′-methoxyflavone}, which was described from N. sativa for the first time, were isolated using column chromatography. The chemical structures of the isolated compounds were determined using UV, PMR, and 13C NMR spectroscopy and mass spectrometry. Methods for qualitative analysis of N. sativa herb by TLC and spectrophotometry were proposed. [ABSTRACT FROM AUTHOR]

Enantiomeric separation of (RS)-Metolazone has been achieved by thin-layer chromatography (TLC) using both direct modes. cyclodextrin, containing hydroxylic group, was utilized as the chiral selector. For enantioseparation, cyclodextrin was used as a chiral additive in the stationary phase in a noncovalent mode and there was no chiral additive in the mobile phase; the native enantiomers were isolated and characterized. Cyclodextrin was also added to mobile phase and there was no chiral selector in the stationary phase. The spots were then isolated and characterized. The effect of the composition of the mobile phase, pH, and temperature was studied for the optimization of successful separation conditions. The spots were located in an iodine chamber. [ABSTRACT FROM AUTHOR]

Siegesbeckiae Herba, a traditional Chinese medicine, originates from Siegesbeckia orientalis, S. glabrescens, and S. pubescens in the Pharmacopoeia of the People's Republic of China. However, accurate identification of decoction pieces from the three plants remains a challenge. In this study, 26 batches of Siegesbeckiae Herba were identified by deoxyribonucleic acid barcoding, and their chemical compositions were determined using ultra‐performance liquid chromatography‐electrospray ionization‐quadrupole time of flight‐mass spectrometry. The results showed that the internal transcribed spacer 2 and internal transcribed spacer 1–5.8 S‐ internal transcribed spacer 2 sequences could distinguish three species. In total, 48 compounds were identified including 12 marker compounds screened for three species using the partial least square discriminant analysis. Among these, two diterpenoids 16‐O‐malonylkirenol and 15‐O‐malonylkirenol, and a novel diterpenoid 15,16‐di‐O‐malonylkirenol were isolated and identified. A convenient method for the identification of Siegesbeckiae Herba was established using kirenol and 16‐O‐acetlydarutoside as control standards by thin‐layer chromatography. Unexpectedly, none of the batches of S. orientalis contained kirenol, which did not meet the quality standards of Siegesbeckiae Herba, suggesting that the rationality of kirenol as a quality marker for S. orientalis should be further investigated. The results of this study will contribute to the quality control of Siegesbeckiae Herba. [ABSTRACT FROM AUTHOR]

Extraction and separation of pigments from spinach leaf is an important experiment in organic chemistry laboratory, conducted at universities. However, in experimental teaching, there have always been problems, such as the use of toxic or controlled reagents, long experiment time, cumbersome experimental steps, and poor experimental results. In this study, the conditions of thin layer chromatography were systematically explored. A variety of reagent combinations, such as n-hexane/anhydrous ethanol and n-hexane/n-butanol, were tested. It was found that the developing agent with the best separation effect was n-hexane/anhydrous ethanol solution, with a volume ratio of 10: 1. The n-hexane/absolute ethanol and n-hexane/n-butanol were also used as eluents to explore column chromatography separation experiments of the pigments from spinach leaf. By using silica gel as the stationary phase, the optimal gradient elution scheme with n-hexane/absolute ethanol as eluent was obtained; whereas, the optimal gradient elution scheme with n-hexane/n-butanol as the eluent was obtained by using neutral alumina as the stationary phase. Following the improvement, the separation effect was enhanced and the amount of reagent was reduced; furthermore, more friendly reagents were used and the teaching time was shortened. [ABSTRACT FROM AUTHOR]

Background and Aim: Antibiotic residues in livestock farming have been identified as a potential cause of antimicrobial resistance in humans and animals. This study aimed to determine whether antibiotic residues were present in the chicken meat, eggs, feces, and feed collected from all four districts in the Mymensingh division of Bangladesh. Materials and Methods: To detect antibiotic residues in the collected samples, qualitative thin-layer chromatography (TLC) and quantitative high-performance liquid chromatography (HPLC) were used. A total of 230 samples were analyzed for antibiotic residues of commonly used 11 antibiotics. Out of these, 40 meat and 40 feces samples were collected from broilers and layers, 30 egg samples from ducks and layers, and 120 feed samples from broilers and layers from the study area. Thin-layer chromatography was used to screen the presence of antibiotic residues; TLC-positive samples were then subjected to further HPLC analysis to determine the residue concentrations. Results: Thin-layer chromatography analysis revealed that 23.5% of the tested samples contained residues from six different antibiotic classes (tetracyclines, quinolones, beta-lactams, sulfonamides, aminoglycosides, and macrolides). Thin- layer chromatography analysis showed that 35% and 25% of the meat samples were positive for residues from the broiler and layer, respectively. About 15% and 30% of layer and duck egg samples had positive residues, respectively. Out of 120 feed samples analyzed, about 15.8% had various antibiotic residues. In addition, feces samples from broilers and layers had 50% and 35% antibiotic residues, respectively. A total of 2.5% meat and 3.3% egg samples had antibiotic residues above the maximum residue limit (MRL). Based on the findings of this study, the highest percentage of oxytetracycline, followed by doxycycline and ciprofloxacin, were detected in feed samples, and oxytetracycline was detected in meat and egg samples. Conclusion: This study clearly showed the misuse of antibiotics in the poultry sector in Bangladesh. Although antibiotic residues below the MRL level are suitable for human consumption, they may result in antimicrobial drug resistance to pathogens. [ABSTRACT FROM AUTHOR]

Nonalcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease worldwide. Liver biopsy remains the gold standard for diagnosis and staging of disease. There is a clinical need for noninvasive diagnostic tools for risk stratification, follow‐up, and monitoring treatment response that are currently lacking, as well as preclinical models that recapitulate the etiology of the human condition. We have characterized the progression of NAFLD in eNOS−/− mice fed a high fat diet (HFD) using noninvasive Dixon‐based magnetic resonance imaging and single voxel STEAM spectroscopy‐based protocols to measure liver fat fraction at 3 T. After 8 weeks of diet intervention, eNOS−/− mice exhibited significant accumulation of intra‐abdominal and liver fat compared with control mice. Liver fat fraction measured by 1H‐MRS in vivo showed a good correlation with the NAFLD activity score measured by histology. Treatment of HFD‐fed NOS3−/− mice with metformin showed significantly reduced liver fat fraction and altered hepatic lipidomic profile compared with untreated mice. Our results show the potential of in vivo liver MRI and 1H‐MRS to noninvasively diagnose and stage the progression of NAFLD and to monitor treatment response in an eNOS−/− murine model that represents the classic NAFLD phenotype associated with metabolic syndrome. [ABSTRACT FROM AUTHOR]

In this work, we extracted, purified, and characterized two active pharmaceutical ingredients, levocetirizine and levosalbutamol (from commercial tablet formulations), and used them as chiral selectors for enantioresolution of gatifloxacin through thin-layer chromatographic (TLC) method. The silica gel was impregnated with a chiral selector for the enantioresolution of gatifloxacin. The mobile phase used was a combination of acetonitrile, methanol, and triethylamine (4:4:2, V/V, pH 9) and (2:6:2, pH 9), respectively, with levocetirizine and levosalbutamol (as chiral selector in stationary phase at pH 5). The detection limit for enantiomers of gatifloxacin was observed to be 4.2 and 4.9 μg spot‒1, respectively, with levocetirizine and levosalbutamol as chiral selectors. This is the first report on levocetirizine and levosalbutamol as chiral selectors for TLC resolution of gatifloxacin enantiomers. [ABSTRACT FROM AUTHOR]

Thin layer chromatography (TLC) is widely used to confirm the formation of the target compound in chemical synthesis. The key issue in TLC is spot identification as it primarily relies on retention factors. Coupling of TLC with surface‐enhanced Raman spectroscopy (SERS), which gives direct molecular information, is an appropriate choice, to overcome this challenge. However, interference from the stationary phase and impurities on the nanoparticles added for SERS measurements significantly degrades TLC‐SERS efficiency. It was found that freezing effectively eliminates such interferences and dramatically improves the performance of TLC‐SERS. In this study, TLC‐freeze SERS is applied to the monitoring of four chemically important reactions. The proposed method can identify the product and side‐products of similar structures, detect compounds with high sensitivity, and provide information of quantities that allows the reliable determination of the reaction time based on kinetic analysis. [ABSTRACT FROM AUTHOR]

To date, the aetiology and molecular mechanisms of the development of fatty hepatosis, which is quite common in mammals, have not yet been sufficiently explained. This pathology requires detailed study not only because of functional disorders of the liver and biliary system, but also because of the high probability of dangerous complications - fibrosis, cirrhosis, or hepatocellular carcinoma. The purpose of this study was to determine marker changes in the phospholipid composition of bile and blood in rats with experimental fatty hepatosis and with the use of corrective therapy. Hepatopathology was modelled in Wistar laboratory rats by intragastric administration of a 4% solution of tetracycline hydrochloride at the rate of 0.25 g/kg body weight for seven days. Using the method of thin-layer chromatography, the phospholipid components of animal bile and blood were studied. It was found that during experimental fatty hepatosis in rats, there was a decrease in the total phospholipid content in bile, mainly due to a decrease in the level of phosphatidylcholine (by 22.4-27.0%), the total fraction of inositol phosphatide and phosphatidylinositol (by 20.0-27.3%), and phosphatidylethanolamine (by 17.5-25.2%). Conversely, the introduction of milk phospholipids in the form of a dietary supplement "FLP-MD" in sick animals contributed to an increase in bile levels of phosphatidylserine by 67.1-99.8%, inositol phosphatide and phosphatidylinositol by 48.6-57.6%, phosphatidylcholine by 38.8-60.2%, phosphatidylethanolamine by 45.6-57.4%, and sphingomyelin by 30.4-46.3%. In the blood of such rats, a significant decrease in the content of phosphatidylcholine, phosphatidylserine, and sphingomyelin was found, which was not observed after administration of the "FLP-MD" dietary supplement to sick animals. In the case of using the supplement in healthy animals, only a 29.3% increase in the blood content of inositol phosphatide and phosphatidylinositol was noted. The determination of the most sensitive indicators in the phospholipid spectrum of blood and bile reveals the features of changes in molecular processes for the development of fatty hepatosis in animals, and also contributes to preclinical tests of the corrective effectiveness of newly created drugs according to established markers. [ABSTRACT FROM AUTHOR]

In this work, a screen-printing method was developed to create porous particle-based materials as layers with specifically designed shape to produce microfluidics systems. Among several tested binding agents, xanthan gum was found to be an excellent choice for a printing mixture thickener as well as a durable binder for the resulting material. In addition to demonstrating control over the shape of the printed microfluidics chips, control over material thickness, wetting characteristics and general method accuracy were also investigated. The applicability of the introduced method was further demonstrated with a development of an exemplary microfluidics chip for quantitative detection of Fe (III), Ni (II), Cu (II), Cd (II), and Pb (II) from a mixed sample at millimolar levels. The novel approaches demonstrated in this article offer new perspective into creating multiplexed on-site chemical analysis tests. [ABSTRACT FROM AUTHOR]

Sorghum is a unique natural food source of 3-deoxyanthocyanidins (3-DA) polyphenols. This work evaluated the effect of acidification on sorghum extracts post pressurized liquid extraction (PLE) and its ability to increase the identification and quantification of 3-DA. The sorghum genotypes included Sumac and PI570366 (bran only) and SC991 (leaf and leaf sheath tissue). The acidification of the PLE extracts was carried out with methanol–HCl solutions at various concentrations (0, 0.5, 1, 2, and 4%, v/v). Changes in color were determined using L*a*b*. The overall phenolic composition was estimated with the total phenolic content and the DPPH free radical scavenging assays. Quantitative and qualitative chromatographic methods determined the phenolic profile. Color analysis showed that the redness and color saturation increased after acidification. No statistical difference was found in the total phenolic content of the acidified extracts, except for SC991, which was increased. There were no differences in the antioxidant capacity following acidification in all samples. For chromatographic analysis, luteolinidin was predominant in the extracts and the 3-DA content increased after acid treatment. However, some flavonoid and phenolic acid concentrations decreased following acid treatment, including taxifolin, quercetin, and chlorogenic acid. Interestingly, 0.5% v/v HCl acidification was sufficient to increase the color, allow the detection of 5-methoxyluteolinidin, and to increase luteolinidin and 7-methoxyapigenidin by at least twofold. [ABSTRACT FROM AUTHOR]