Current Issue : October-December Volume : 2026 Issue Number : 4 Articles : 5 Articles
Arachidonate 5-lipoxygenase (ALOX5) is a key enzyme implicated in several inflammatory disorders, including asthma and allergic rhinitis. Despite its therapeutic importance, only one compound is currently approved as an ALOX5 inhibitor in the United States, highlighting the urgent need for new drug candidates. Progress in this area is often hindered by conventional bioassays, which can be labor-intensive, costly, and unsuitable for complex mixtures. To overcome these challenges, we developed a simple thin-layer chromatography (TLC) bioautographic assay for the rapid detection of ALOX5 inhibitors in natural extracts, a rich source of pharmacologically active compounds. The method exploits the oxidative coupling of 3-methyl-2-benzothiazolinone hydrazone (MBTH) with 3-(dimethylamino)benzoic acid (DMAB) during the ALOX5-catalyzed conversion of arachidonic acid, producing a colored indamine dye. Experimental parameters influencing chromogenic reaction were investigated and optimized to minimize reagent consumption while ensuring accuracy and sensitivity of the method. The assay was then applied to a panel of natural products and to crude mushroom extracts, enabling the rapid identification of several active compounds within complex extracts, including the dual COX2/ALOX5 inhibitor 3α-acetylpolyporenic acid A. Easy to implement, cost-efficient, and well suited for screening and bioguided fractionation, this TLC bioassay provides a powerful tool to accelerate the discovery of novel anti-inflammatory compounds....
Toxicological testing for drugs of abuse (DOAs) is an essential tool for healthcare practitioners and law enforcement agencies. Oral fluid (OF) is an alternative biological fluid for detecting recent DOA intake and is widely employed in forensic investigations. In the current study, a relatively novel and “green” fabric phase sorptive extraction (FPSE) procedure for sample preparation was coupled to liquid chromatography–tandem mass spectrometry (LC–MS/MS) to provide simplicity, cost-effectiveness, rapidity, low solvent consumption, and high analytical performance for the quantitative determination of ten commonly encountered DOAs and metabolites: amphetamine, benzoylecgonine, cocaine, codeine, ecgonine methyl ester, methadone, methamphetamine, 3,4-methylenedioxyamphetamine, 6-monoacetylmorphine, and morphine. The FPSE procedure was optimized by testing different filters, pH, extraction time, and solvents. The validated method demonstrated excellent linearity for all analytes, selectivity, acceptable precision, and high sensitivity (ranges for limits of detection (LODs) and quantification (LOQs) were 0.01–2 ng/mL and 0.03–6 ng/mL, respectively). Autosampler and short-term freeze stability exceeded 95% and 90% for all analytes, respectively. Overall, the combination of FPSE with LC–MS/MS provided a sensitive, selective, and environmentally friendly innovative analytical approach for the determination of DOA in OF and is suitable for both screening and confirmatory forensic and clinical applications....
Background/Objectives: Vancomycin hydrochloride (HCl) for injection is a vital antibiotic for severe infections. Vancomycin is an indispensable first-line antibiotic for life-threatening infections like methicillin-resistant Staphylococcus aureus (MRSA) bacteremia and serves as a key oral agent for severe Clostridium difficile infection. This makes rigorous quality monitoring essential. Concerns about the efficacy of certain generic vancomycin HCl products have prompted regulatory agencies to increase post-market evaluations to ensure patient safety. Aligned with these efforts, this study aimed to comparatively evaluate the potency and quality of five randomly procured generic intravenous vancomycin HCl products marketed in Saudi Arabia. Methods: Using both microbiological and chemical methodologies as recommended by the US Pharmacopeia (USP) guidelines. Results: The microbiological assay, utilizing the USP “Antibiotics—Microbial Assay” method using Bacillus subtilis ATCC 6633 via the agar diffusion technique, demonstrated a strong linear correlation (R2 > 0.98) between inhibition zone diameters and vancomycin concentration. All five tested generics products showed compliance (~ 105%) with USP <81> biological activity standards. For chemical quantification, a High-Performance Liquid Chromatography-Diode Array Detector (HPLC-DAD) method was developed and validated according to ICH Q2(R2) guidance. This method showed excellent linearity (R2 = 0.998), accuracy (96.9–102%), and good precision. Conclusions: Both methods confirmed the potency of the tested generics within USP limits. However, minor variations observed between microbiological and chemical results highlight the importance of employing complementary techniques for comprehensive quality assessment. These findings underscore the importance of robust regulatory frameworks and ongoing post-market surveillance to ensure the continued safety, efficacy, and availability of quality-assured generic antibiotics in the Saudi market....
This study establishes and validates a sustainable reverse-phase “high-performance thin-layer chromatography (HPTLC)” methodology for the concurrent assay of aceclofenac (ACC) and paracetamol (PCT) in their fixed-dose combination (FDC) tablets. A green developing system with a 70:30 (v/v) ratio of ethanol and water was used to assess ACC and PCT simultaneously. The methodology was validated for numerous validation parameters following standard regulatory guidelines. The method’s greenness and whiteness profiles were assessed using four different metrics: “the analytical eco-scale (AES), chloroform toxicity (ChlorTox), the analytical GREEnness (AGREE) and the blue applicability grade index (BAGI)”. The suggested method was linear for both drugs in the 25–1,200 ng/band level. Following validation, the suggested method was determined to be precise, accurate, robust, sensitive, and sustainable. The results from all the greenness and whiteness tools, such as AES (93), ChlorTox (0.72 g), AGREE (0.75), and BAGI (85), demonstrated that the developed method had a notably greener and whiteness profiles. The ACC and PCT levels in commercial FDC tablets were found to be within the limit of 100 ± 2 % using the suggested methodology. The investigation’s findings demonstrated that the suggested technique could accurately analyze the levels of ACC and PCT in commercial FDC tablets....
Propylene glycol (PG), a generally recognized as safe ingredient widely used in pharmaceuticals, cosmetics, and food products, has not previously been investigated as a green solvent for high-performance liquid chromatography (HPLC). This study reports the first application of PG as an organic modifier in reversed-phase HPLC. A simple, eco-friendly, and efficient isocratic method was developed for the simultaneous determination of acetaminophen and caffeine in combination tablets, with effective separation of the impurity 4-aminophenol. Using a 10-cm C18 column and a mobile phase comprising 25 % (v/v) PG in water, adjusted to pH 4.0 with glacial acetic acid, at 50 °C and a flow rate of 2.0 mL/min, complete separation was achieved within 2 min under a backpressure below 200 bar and detection at 275 nm. The method was fully validated and provided results consistent with the United States Pharmacopeial method. Greenness evaluation using AGREE and GAPI tools confirmed superior environmental performance, with a BAGI score of 85.0, demonstrating high practicality. Owing to low volatility, flammability, and toxicity, along with water miscibility, UV transparency, biodegradability, and renewable sourcing, PG represents a green and sustainable alternative to conventional volatile HPLC solvents without compromising analytical performance or reliability....
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