ABSTRACT Cardiovascular diseases remain a leading cause of mortality, and these are frequently treated with a combined therapy of statins and fenofibrate (FFB) in the treatment of lipids, which reveals a synergic effect. The primary aim of this study was to develop and validate a robust high‐performance liquid chromatography (HPLC) method for the quantification of pravastatin, rosuvastatin, atorvastatin, and FFB in bulk and solid oral dosage forms based on analytical quality by design (AQbD) and comprehensive green analytical chemistry (GAC) metrics. Systematic optimization was carried out by central composite design (CCD) experiment. The chromatographic separation was achieved using a Waters Sunfire C18 column (150 × 4.6 mm 2 , 5 µm) with 0.1% acetic acid: acetonitrile (23:77 v/v) as the mobile phase, a flow rate of 0.9 mL/min, and UV detection at 250 nm. The method was validated in accordance with ICH Q2(R2) guidelines. Moreover, the ecological and practical consequences of the procedure were assessed using a multi‐metric suite of GAC tools, including analytical Eco‐Scale, green analytical procedure index (GAPI), Analytical GREEnness (AGREE), red analytical performance index (RAPI), blue applicability grade index (BAGI), and analytical green star area (AGSA). The optimized experimental design allowed baseline separation of all four targeted drugs in an analysis time of less than 10 min. The validated method showed good linearity ( R 2 > 0.999) and high precision and accuracy, with recovery rates ranging from 98.21% to 99.67% for all analytes. The multi‐metric sustainability assessment gave an analytical Eco‐Scale score of 90, indicating the procedure is an excellent green analysis by supporting the use of minimal hazardous solvents and reducing energy consumption without loss of analytical efficiency. The method was successfully used to quantitatively evaluate the commercial binary formulations. This powerful and high‐throughput chromatographic method combines the benefits of statistical optimization and a comprehensive multidimensional greenness evaluation, making it an ideal and eco‐friendly solution for regular quality control testing of complex antihyperlipidemic combination products.
ABSTRACT In the present study, a simple and selective high‐performance liquid chromatography (HPLC) method for Olmesartan Medoxomil (OLM) and Azelnidipine (AZL) was developed and subsequently validated by reverse‐phase LC. Separation was achieved on an Agilent ZORBAX C18 (150 mm × 4.6 mm, 5 µm) at Room temperature using 0.05 M ammonium formate buffer (pH 3.5) and methanol (30:70 %v/v) as the mobile phase in isocratic mode, and the chromatogram was developed at 262 nm. Under the optimized chromatographic conditions, the retention times of OLM and AZL were observed at 3.71 and 5.39 min, respectively. A strong linear detector response was obtained over concentration ranges of 10–30 µg/mL for OLM and 4–12 µg/mL for AZL, with correlation coefficient ( R 2 ) values of 0.999 for both analytes. The mean recovery of the accuracy study was between 99.33% and 101.43%, respectively. The results obtained for precision, limit of detection, limit of quantification, and robustness were within limits and validated under different stress conditions as per ICH guidelines. Both drugs exhibited susceptibility to degradation under acidic, basic, oxidative, photolytic, and thermal stress conditions. Forced degradation studies confirmed its reliability for drug analysis, and an Analytical Greenness outcome highlighted its environmental sustainability as compared to other reported methods.
ABSTRACT Berberine (BBR) and bromocriptine (BM) exhibit significant therapeutic potential for neurodegenerative diseases, including Parkinson's disease; however, their clinical application is limited by poor stability, rapid clearance, and lack of unified platform for simultaneous evaluation. This study developed and validated a simple, reliable, and economical RP–HPLC with diode‐array detection–based method for their simultaneous quantification, adhering to ICH and US FDA guidelines. The method demonstrated excellent selectivity, linearity, precision, accuracy, and reproducibility and was successfully translated into bioanalytical method for plasma analysis. Forced degradation studies validated the method's ability to indicate stability under acidic, alkaline, oxidative, and thermal stress conditions. Polydopamine (PDA) nanoparticles (NPs) were developed to co‐encapsulate BBR and BM, exhibiting favorable physicochemical characteristics, high drug loading, and sustained in vitro release following diffusion‐controlled kinetics. Overall, the validated analytical and bioanalytical method verified its versatility across formulation development, stability assessment, release kinetics, and pharmacokinetic studies, whereas the PDA NP system demonstrated sustained delivery and improved pharmacokinetic performance, supporting its potential for further preclinical and pharmacodynamic studies for various neurodegenerative diseases.
ABSTRACT A novel reverse phase‐liquid chromatography method was therefore developed and then validated for the separation and characterization of impurities and byproducts, and the degradation products of drugs doxecitine and doxribtimine were further identified using liquid chromatography–mass spectrometry method analysis. Here method optimization was carried out using the stress‐degraded samples along with the spiked impurity solutions. The chromatographic separation was achieved on a Waters X‐Bridge C18 column of dimensions (150 mm × 4.6 mm, 3.5 µm), which is equipped with a PDA detector. At a flow rate of 1.0 mL/min and a detection wavelength of 257 nm, an isocratic mobile phase of water was pH‐adjusted to 3.0 with formic acid and methanol (70:30, v/v). The method here demonstrated the satisfactory performance of parameters like accuracy, precision, and linearity for the drugs doxecitine, doxribtimine, and their four impurities. The forced degradation studies confirmed that the stability‐indicating nature of the method. The seven degradation products were successfully characterized using liquid chromatography–mass spectrometry method, and sensitivity parameters including like LOD and LOQ were adequately established. All the analytes exhibited strong linearity along with a correlation coefficient of 0.999, by confirming the reliability of the method for the quantitative analysis of doxecitine, doxribtimine, and the related substances.
ABSTRACT A sustainable and environmentally benign reversed‐phase high‐performance liquid chromatography method was developed for the simultaneous determination of six widely used anti‐cold drugs: pseudoephedrine hydrochloride, paracetamol, caffeine, cetirizine dihydrochloride, guaifenesin, and ibuprofen. The method was designed in accordance with green analytical chemistry concepts, allowing the simultaneous analysis of multiple components in a single chromatographic run within a short analysis time. Notably, the procedure eliminates the need for derivatization or prior sample preparation and operates with relatively low energy requirements. Chromatographic separation and quantification were achieved using a reversed‐phase C18 column. The mobile phase system consisted of ethanol as solvent A and 0.1% aqueous acetic acid as solvent B, delivered through a simple gradient elution program at a flow rate of 1.2 mL/min. Detection was performed using an ultraviolet detector set at 215 nm. Validation of the developed method was carried out following International Council for Harmonization guidelines, confirming its linearity, selectivity, sensitivity, accuracy, precision, and robustness. The applicability of the method was demonstrated through successful analysis of 12 different pharmaceutical formulations, including tablets, capsules, and oral drops. The results showed excellent selectivity and accuracy, with no interference observed from common excipients. Overall, the proposed method offers a reliable and environmentally friendly alternative for routine quality control analysis of the investigated drugs. Evaluation of its environmental impact using the National Environmental Methods Index, Green Analytical Procedure Index, and Analytical GREEnness Metric Approach tools revealed a high level of greenness, with an Eco‐Scale score of 92, indicating excellent environmental compatibility.
ABSTRACT A selective, robust, and sensitive liquid chromatography–tandem mass spectrometry analytical procedure was developed to monitor trace amounts of potentially carcinogenic N ‑nitroso desmethyl chlorpromazine (NNO‑DM‑CPZ) impurity in chlorpromazine hydrochloride injection (25 mg/mL). Using specific multiple reaction monitoring (MRM) in positive electrospray ionization mode and a multistep gradient elution program (mobile phase A and B: 0.1% formic acid and methanol, respectively) employing an XBridge C18 column from Waters, the method achieved acceptable separation from chlorpromazine, its related substances, and matrix components. Validation was performed at the 0.1325 µg/mL specification limit in accordance with International Council for Harmonisation guidelines, evaluating specificity, sensitivity, accuracy, precision, and linearity. The limit of detection and limit of quantification (LOQ) were established as 0.0066 and 0.0133 µg/mL, respectively, with excellent linearity across 0.0133–0.1988 µg/mL (LOQ to 150% of specification). This method ensures reliable detection of NNO‑DM‑CPZ impurity at trace levels in chlorpromazine HCl injection (25 mg/mL).
ABSTRACT The increasing regulatory concern regarding nitrosamine drug substance‐related impurities necessitates the development of highly sensitive and selective analytical methods. This study presents a sensitive and environmentally sustainable liquid chromatography coupled with tandem mass spectrometry method for the determination of N‐ nitrosodesbutyl dronedarone impurity in dronedarone hydrochloride. To the best of our knowledge, this is the first validated analytical method reported for the trace‐level determination of this impurity. The analytical procedure employs a simplified sample preparation approach without derivatization using a water–methanol mixture containing 0.1% formic acid. The proposed method demonstrated excellent sensitivity, with a limit of detection of 0.0618 ppm and a limit of quantification of 0.1875 ppm, together with outstanding linearity (coefficient of determination ≥0.999). Accuracy, precision, and robustness were found to be compliant with the requirements of the International Council for Harmonization Guideline Q2(R2) for Validation of Analytical Procedures, confirming the suitability of the method for trace‐level impurity determination. The environmental sustainability of the method was systematically evaluated using the Analytical GREEnness metric approach, the Complex Green Analytical Procedure Index, and the Analytical Eco‐scale assessment tools, which indicated a favorable environmental profile. This is primarily attributed to minimal sample consumption, reduced solvent usage, elimination of derivatization, and a simplified analytical workflow. However, the use of organic solvents and energy‐intensive liquid chromatography–mass spectrometry instrumentation remains a limitation. Compared with previously reported liquid chromatography–mass spectrometry methods, the proposed method offers a shorter analysis time and a simplified analytical procedure. Overall, the developed analytical method provides an effective balance between analytical performance and environmental sustainability, making it suitable for routine pharmaceutical quality control applications while supporting the principles of Green Analytical Chemistry.
ABSTRACT Bupropion is an antidepressant widely used for the treatment of major depressive disorder, seasonal affective disorder, and as an aid in smoking cessation. The presence of nitrosamine drug substance‐related impurities in Bupropion drug substance raises potential safety concerns due to their carcinogenic nature. In this study, Bupropion‐associated two N‐nitrosamine impurities were identified and evaluated. Acceptable intake limits were established using the carcinogenic potency categorization approach, classifying the impurities under potency Category 5. A sensitive and selective liquid chromatography triple quadrupole mass spectrometric method was developed and optimized in agreement with International Council for Harmonisation Guideline Q14 procedures for the trace‐level quantification of Bupropion nitrosamine drug substance‐related impurities. Chromatographic separation was achieved using an Agilent Poroshell 120 Ethylene Crosslinked C18 column (150 mm × 2.1 mm, 2.7 µm) with gradient elution, employing 0.1% formic acid in water and acetonitrile as mobile phases at a flow rate of 0.4 mL/min and column temperature of 40°C. The method was designed based on an Analytical Target Profile, incorporating risk assessment and structured reporting. Method validation and robustness were carried out following International Council for Harmonisation Guideline Q2(R2) guidelines, demonstrating acceptable specificity, accuracy, precision, and sensitivity. The environmental sustainability of the method was evaluated using the Analytical GREEnness metric approach, the Modified Green Analytical Procedure Index, and the Blue Applicability Grade Index tools, confirming its green and sustainable nature. This study supports the United Nations Sustainable Development Goals, Goal 3: Good Health and Well‐Being, and Goal 9: Industry, Innovation, and Infrastructure by ensuring pharmaceutical safety through advanced impurity analysis and promoting environmentally sustainable analytical practices.
ABSTRACT A micellar electrokinetic chromatography (MEKC) method was developed and validated for the simultaneous determination of dapagliflozin (DAPA) and metformin (MET) in pharmaceutical formulations. Due to the markedly different physicochemical properties of the two antidiabetic drugs, conventional capillary zone electrophoresis failed to provide adequate selectivity. This limitation was overcome by introducing MEKC, enabling the selective separation of a neutral and a highly polar cationic analyte. Following an initial one‐factor‐at‐a‐time screening, critical experimental parameters were systematically optimized using a Box–Behnken design, evaluating the influence of sodium dodecyl sulfate (SDS) concentration, separation voltage, and capillary temperature on DAPA migration time, MET peak symmetry, and generated current. Optimized separation was achieved using a 25 mM borax buffer (pH 9.3) containing 38 mM SDS, a separation voltage of 28 kV, and a capillary temperature of 25°C, with ultraviolet detection at 210 nm. Under these conditions, complete separation was obtained within 7 min. The method exhibited good linearity over concentration ranges of 0.02–0.20 mg mL − 1 for DAPA and 0.1–1.00 mg mL − 1 for MET, with satisfactory precision, accuracy, and sensitivity. Robustness evaluation using a Plackett–Burman design confirmed the stability of the method. The method was successfully applied to the analysis of commercial fixed‐dose combination tablets, yielding assay results consistent with labeled claims. The developed method represents a rapid, reliable, and environmentally favorable alternative to conventional chromatographic approaches for the routine quality control of fixed‐dose antidiabetic formulations.
ABSTRACT The global prevalence of obesity and its related metabolic dysfunctions underscores the pressing demand for novel therapeutic interventions. Polyalthia longifolia is reported to have promising phytopharmaceutical and nutraceutical potential for managing dyslipidemia. The present study reports a simple, selective, and green LC–MS/MS analytical method for the simultaneous quantification of the potential anti‐adipogenic and anti‐dyslipidemic phytochemicals, namely, N‐016‐0014, N‐016‐0015, N‐016‐0016, and N‐016‐0017, derived from the 4655‐enriched fraction (4655‐EF) of P. longifolia leaves. The 4655‐EF was formulated using a bioactivity‐directed green, sustainable, and eco‐friendly supercritical fluid extraction process, tailored for scalability and commercial viability. An optimized liquid–liquid extraction (LLE) protocol was employed for plasma sample preparation, ensuring optimum recovery of analytes with minimal solvent usage. Chromatographic separation was achieved on a Waters Symmetry C 18 column under a reverse‐phase gradient elution, followed by mass spectrometric detection in negative electrospray ionization (ESI) mode using multiple reaction monitoring (MRM). The method demonstrated excellent sensitivity, selectivity, and reproducibility, with clear chromatographic resolution of isomeric analytes. Greenness of the analytical workflow was assessed using Analytical GREEnness (AGREE), green analytical procedure index (GAPI), and AGREEprep greenness assessment metrics, yielding a cumulative score in the Green Zone, confirming its environmental sustainability. The method was successfully applied to a preclinical pharmacokinetic study in rats, establishing its suitability for translational bioanalysis.
Pesticides are used to control, prevent, or eliminate pests that threaten crops, public health, and stored products. Malathion, an organophosphate pesticide, remains a priority contaminant across water, food, and soil, leading to environmental contamination and bioaccumulation in ecosystems. Their widespread and often indiscriminate use has raised significant concerns. This comprehensive review presents recent advances in the detection of Malathion using spectrometric, chromatographic, and biosensor techniques. Spectrometric methods deliver rapid screening with minimal sample preparation. Chromatographic workflows provide confirmatory quantification and separation, whereas immunoassays are required for pesticide residue quantification or screening. Electroanalytical sensors and advanced biosensors can be categorized into different types, such as non‐enzymatic, colorimetric, fluorescence‐based, including metallic organic framework (MOF‐based), aptamer‐based, and molecular imprinted polymer (MIP‐based), offering low‐cost, real‐time monitoring of samples. Future advancements in Malathion detection by integrating nanomaterials, microfluidics, and aptamer or antibody‐based recognition elements in biosensors, enabling faster, more selective, and ultra‐sensitive detection. The convergence of spectrometric, chromatographic, and biosensor technologies promises comprehensive tools for environmental monitoring, food safety, and health diagnostics in the upcoming years.
ABSTRACT Bosutinib (BST), a 4‐anilino‐3‐quinolinecarbonitrile derivative, is a tyrosine kinase inhibitor approved for the treatment of chronic myelogenous leukemia. To assess the chemical stability of BST and elucidate its degradation pathways, forced degradation studies were conducted in accordance with International Council for Harmonisation quality guidelines Q1A(R2). Chromatographic analysis under oxidative stress conditions revealed the formation of two major degradation products (DP's), eluting at relative retention times of approximately 1.09 and 1.14, with respective abundances of 15% and 76%. These were isolated using preparative high‐performance liquid chromatography and structurally characterized using liquid chromatography–mass spectrometry and nuclear magnetic resonance spectroscopy. LC–mass spectrometry (MS) analysis indicated mass increases of +16 and +32 Da, consistent with mono‐ and di ‐oxidation, respectively. Nuclear magnetic resonance (NMR) data ( 1 H, 13 C, and 2D experiments) localized the oxidative modifications to the piperazinyl‐propoxy side chain and the aromatic methoxy groups. The identification and structural elucidation of these oxidative DP's are critical for understanding the degradation pathways of BST. This work underscores the importance of comprehensive impurity profiling not only for regulatory compliance and formulation development but also for ensuring drug product safety, particularly in oncology therapies where patient risk tolerance is low.
ABSTRACT The widespread contamination of water by sulfamethazine (SMZ) poses risks to ecosystems and public health. Herein, we develop photoresponsive magnetic molecularly imprinted polymers (Fe 3 O 4 @MIPs) featuring a magnetic Fe 3 O 4 core and an azobenzene‐based functional monomer (MAPDIA). The material exhibits high selectivity for SMZ with an imprinting factor of 2.09 and a maximum adsorption capacity of 25.06 mg·g −1 . Adsorption follows the Langmuir isotherm, indicating homogeneous monolayer binding, and reaches equilibrium within 60 min. Leveraging the reversible trans – cis photoisomerization of azobenzene under alternating 365 and 440 nm irradiation, the polymer enables light‐controlled uptake and release of SMZ with good reversibility over multiple cycles. When applied as a sorbent for solid‐phase extraction from real environmental water samples, Fe 3 O 4 @MIPs provide SMZ recoveries ranging from 88.5% to 95.7%, demonstrating their potential for smart antibiotic monitoring and remediation.
ABSTRACT Cardiovascular diseases are the leading cause of worldwide mortality, often supported by intricate dyslipidemic patterns of high levels of low‐density lipoprotein cholesterol and triacylglycerol. HMG‐CoA reductase inhibitors (statins) and ezetimibe can be used synergistically to treat these pathologies, as they target distinct metabolic pathways to reduce residual atherosclerotic risk. This research presents the design and multivariate optimization of a high‐performance liquid chromatographic system for the simultaneous determination of rosuvastatin, atorvastatin, simvastatin, and ezetimibe. The critical process parameters (i.e., the ratio of organic modifier and volumetric flow rate) were modeled using a three‐level central composite design to optimize chromatographic resolution and reduce overall analytical cycle time. The better separation was obtained on a Waters Sunfire C18 stationary phase (150 mm × 4.6 mm; 5 mm) using an isocratic elution system of 0.1% (v/v) aqueous acetic acid: acetonitrile (40:60, % v/v), at a flow rate of 1.4 mL/min, with spectrophotometric detection at 240 nm. The methodology was rigorously validated in line with ICH guidelines, demonstrating high selectivity, precision, accuracy, and linearity. Moreover, the method was critically evaluated with respect to green analytical chemistry parameters, ensuring the minimization of hazardous waste and solvent consumption. This proven framework, when successfully applied to binary marketed formulations, provides a robust, sustainable, and high‐throughput analytical methodology for routine quality control and for quantifying drug substances in multicomponent complex matrices.
ABSTRACT A rapid reversed‐phase liquid chromatographic method was developed for the separation and quantification of major whey proteins in dietary supplements using a poly(butyl methacrylate–co–ethylene dimethacrylate) monolithic column. The column structure was characterized by scanning electron microscopy, revealing a homogeneous porous network composed of ∼1 µm polymer globules and large flow‐through pores, which together provide high permeability and low backpressure, suitable for fast separations. Under a steep acetonitrile gradient, α‐lactalbumin (α‐LA), bovine serum albumin (BSA), and β‐lactoglobulin (β‐LG) were separated within 4 min, showing good peak symmetry and repeatable retention factors. The method exhibited excellent linearity ( R 2 > 0.99) over the concentration range of 0.025–0.91 mg/mL, with limits of detection ranging from 2.7 µg/mL for BSA to 6.2 µg/mL for β‐LG. Furthermore, analysis of three commercial whey protein supplements showed high intermediate precision (evaluated over three different days), with relative standard deviations below 6.0% for the major proteins (α‐LA and β‐LG) and under 12.5% for the minor component (BSA). Spike‐and‐recovery experiments confirmed the accuracy and reliability of the proposed method, yielding recovery rates ranging from 97% to 113%. β‐LG was the predominant protein, followed by α‐LA and minor amounts of BSA. The proposed approach provided fast analysis and low consumption of solvent and sample, with acceptable chromatographic efficiency, demonstrating that polymeric monolithic microbore columns constitute a potential alternative to packed columns for routine quality control of whey‐based dietary supplements.
ABSTRACT Postmenopausal osteoporosis (PMOP) is characterized by progressive bone loss and microarchitectural deterioration. However, the metabolomic characterization of localized metabolic remodeling in bone tissue remains limited by its structural complexity and chemical heterogeneity. In the study, a bone‐oriented dual‐platform UHPLC‐MS analytical workflow was established, integrating untargeted metabolomics, targeted quantification, and network pharmacology‐assisted pathway prioritization to characterize metabolic remodeling in PMOP and its modulation by Gushudan (GSD). Using biphasic extraction in combination with complementary HILIC (ACQUITY UPLC Amide) and RP (BEH C18) UHPLC‐Q‐Orbitrap HRMS platforms, expanded coverage of polar and non‐polar metabolites in rat bone tissue was achieved. In ovariectomized rats, pronounced metabolic perturbations in bone were revealed by this workflow, together with a partial shift toward metabolic normalization following GSD treatment. A total of 33 differential metabolites were putatively annotated, with pathway analysis highlighting branched‐chain amino acid (BCAA) metabolism as a major perturbed pathway. Integration with network pharmacology prioritized branched‐chain amino acid transaminase 2 (BCAT2) as a candidate regulatory target. To validate this pathway, a targeted UHPLC‐MS/MS analysis for BCAAs and branched‐chain keto acids in bone tissue was developed and fully validated, demonstrating satisfactory selectivity, linearity, precision, accuracy, recovery, matrix effect, and stability. Quantitative analysis confirmed BCAA remodeling in osteoporotic bone and its partial normalization after GSD treatment. Western blotting further supported BCAT2 dysregulation in PMOP bone tissue and its reversal by GSD, while molecular docking and enzyme inhibition assays suggested that salvianolic acid D and naringenin may contribute to BCAT2‐related modulation. This study establishes an integrated analytical strategy for resolving localized metabolic alterations in bone tissue and identifies BCAT2‐associated BCAA remodeling as a candidate target modulated by GSD in PMOP.
This article presents the development and validation of two new stability-indicating RP-HPLC methods for the determination of two related substances (RS) and the assay of amifampridine phosphate (AMP) via forced degradation and mass balance studies. In RS method, AMP was resolved adequately from its two RS, namely, 4-aminopyridine and 3,4,5-triaminopyridine on YMC Triart C18 (250 & times; 4.6 mm, 3 & micro;m) column. Ammonium acetate solution (2.3 g/L) with its pH adjusted to 9.0 +/- 0.05 was used as buffer. Gradient elution was implemented with the use of mobile phase A (buffer) and mobile phase B (buffer and acetonitrile in 80:20 v/v). The flow rate, injection volume, column temperature, and wavelengths were maintained as 0.7 mL/min, 20 & micro;L, 40 degrees C, and 240 nm, respectively. Additionally, an assay method for AMP was also developed using the same column. Both methods underwent validation in accordance with ICH guidelines. In the RS method, the limit of detection and limit of quantitation values were 0.010% and 0.031%, respectively. The correlation coefficient values exceeded 0.995 in both methods. The recoveries ranged from 93.5% to 100.7% for the RS method and from 100.1% to 101.1% for the AMP assay method.
Regulatory agencies, including the US Food and Drug Administration and the International Conference on Harmonization, are currently focusing on the assessment of various pharmaceuticals in the presence of their contaminants. Consequently, a green high-performance liquid chromatographic method was developed, optimized, and validated for the simultaneous separation and quantitation of a quaternary mixture of Paracetamol (PAR) and Aspirin (ASP) in the presence of the toxic impurity of PAR, 4-aminophenol, and the major impurity of ASP, salicylic acid (SA). The optimized separation of the studied compounds was performed on a Kinetex C18 column (100 mm & times; 4.6 mm I.D., particle size 2.6 & micro;m) at ambient temperature using 0.05 M sodium dodecyl sulfate 0.1% ortho-phosphoric acid:methanol (70.0:30.0, v/v) with a flow rate of 1.0 mL/min, followed by UV detection at 230.0 nm. Linear regressions were achieved at concentrations ranging from 1.0-50.0 & micro;g/mL for paracetamol and salicylic acid and from 1.0-30.0 & micro;g/mL for aspirin and 4-aminophenol. The suggested approach was confirmed to comply with ICH regulations and was effectively utilized for the quantification of a PAR and ASP binary mixture in a dosage form, achieving a distinct separation of the two medicines from their contaminants. Finally, the eco-friendliness of the suggested approach was validated via the Analytical Eco-scale, the Green Analytical Procedure index, and the Analytical GREEnness metric approach tools.
A rapid, sensitive, and selective LC-MS/MS method using multiple reaction monitoring (MRM) acquisition mode was developed and validated for the simultaneous determination of 2-chloro-1,3-bis(dimethylamino)trimethinium hexafluorophosphate (HFP), methyl para-toluenesulfonate (MPTS), ethyl para-toluenesulfonate (EPTS), isopropyl para-toluenesulfonate (IPTS) impurities in etoricoxib active pharmaceutical ingredient (API). The method was established through systematic mass-based identification and chromatographic optimization, followed by full validation in accordance with ICH guidelines. Chromatographic separation was achieved on an ACE phenyl column using an ammonium acetate buffer and acidified methanol under gradient conditions, with MRM detection in positive ESI mode. The method was linear (correlation coefficients [r] >= 0.99), precise (%RSD < 6%), accurate (recoveries 78.7%-110.9%), and robust, with low ppm limits of detection and quantification. The method is suitable for routine quality control and regulatory applications.
Paper-based microfluidic devices offer low-cost, portable alternatives for point-of-care analyses; however, their use for detecting specific analytes directly from whole blood remains limited by the challenge of on-paper plasma extraction. In this study, we propose a three-dimensional origami paper-based microfluidic platform that incorporates electrodes to generate dielectrophoresis. This platform facilitates the rapid enrichment of plasma and subsequent colorimetric detection of ephedrine. The integrated dielectrophoresis module facilitates the preferential retention of red blood cells under an applied nonuniform electric field, generating a clarified plasma fraction that traverses into a multilayer detection zone. In this instance, ephedrine is detected via a modified Chen-Kao reaction compatible with paper substrates, resulting in the formation of a characteristic purple chelate within minutes. Tests performed using fresh Wistar rat blood spiked with ephedrine demonstrate the feasibility of rapid on-paper analysis, with the device offering advantages in fabrication simplicity, reagent storage, and portability as well. While further optimization is required to meet clinically relevant limits of detection, the system establishes a compact platform capable of coupling electrical blood processing with colorimetric sensing, highlighting its potential for point-of-care toxicological screening in resource-limited settings.
