Current Pharmaceutical Analysis - Volume 20, Issue 8, 2024

Alzheimer's disease (AD) impacts a total of 30 million individuals worldwide, resulting in the impairment of brain cells. Despite the approval of medications, there are still poor results and adverse effects that continue to exist, which has led to continued research for more effective treatments.

In this study prioritize the medicinal plants and their bioactive chemicals to attract researchers and pharmaceutical companies interested in producing powerful herbal medicines and semi-synthetic drugs for the treatment of Alzheimer's disease, although minimizing any potential adverse effects.

This review investigate the effective use of medicinal plants and their phytochemicals in the treatment of AD to manage its growth and relieve symptoms via improving cognitive deficits.

These medicinal plants and their phytochemicals contribute to the treatment of AD by protecting against cell damage induced by beta amyloid, improving memory and learning abilities, functioning as nerve tonics, and exhibiting strong antioxidant and anti-inflammatory activities. Furthermore, they have demonstrated therapeutic benefits in the management of AD. The finding suggests that several phytoconstituents/ plant metabolites are present in numerous anti-Alzheimer's plants known for their anti-Alzheimer's properties such as rosmarinic acid, quercetin, kaempferol, gallic acid, β-sitosterol, oleic acid and linalool. In addition, this article emphasizes the anti-Alzheimer's disease significance of various important phytochemicals.

The review proposes that medicinal plants and their bioactive phytochemicals hold potential as a viable alternative treatment for AD. The utilization of these medicinal plants can improve memory and decrease the likelihood of developing Alzheimer's disease in the future.

Anticancer herbal drugs have gained significant attention in pharmaceutical research due to their complex chemical profiles and multifaceted therapeutic effects. Electrochemical analysis has emerged as a powerful tool for studying these compounds, offering unique insights into their behavior and properties.

This review examines recent advances in the electrochemical analysis of five key anticancer herbal drugs: emodin, rutin, berberine, shikonin, and sophoridine. Various electrochemical techniques, including cyclic voltammetry, differential pulse voltammetry, and square wave voltammetry, are discussed in relation to their application in detecting and characterizing these compounds.

Significant progress has been made in developing highly sensitive and selective electrochemical sensors for these herbal drugs. Nanomaterial-modified electrodes have consistently improved detection limits and expanded linear ranges. Compound-specific innovations in electrode modifications and measurement techniques have been tailored to the unique electrochemical properties of each drug.

Electrochemical analysis of anticancer herbal drugs has advanced substantially, offering powerful tools for studying and utilizing these compounds in cancer research and treatment. Future directions include the development of multi-analyte sensors, integration with microfluidic technologies, and application of artificial intelligence for data analysis. Challenges remain in improving the stability of modified electrodes and standardizing protocols for sample preparation and analysis.

Analytical methods have an essential function in the healthcare sector, particularly when it emanates from the creation and approval of medications. These methods are essential for identifying the active ingredients, ensuring the purity of compounds, and quantifying the existence of any impurities or degradation products.

The objective of the research article is to discuss an analytical method available for the drug Onychomycosis, which is indeed crucial in treating nail infection, to confirm the efficacy and quality of pharmaceutical products. Among various analytical techniques available, UV Spectroscopy, RP-HPLC (high performance-liquid chromatography) and tandem mass spectrometry are normally employed due to their speed and accuracy.

Literature surveys typically reveal the predominance of UV, RP-HPLC and LC-MS/MS methods for estimating azole derivatives due to their established reliability, sensitivity, and applicability to an extensive range of compounds. Researchers often select the most suitable method based on factors such as sample complexity, sensitivity requirements, and available instrumentation.

This present art states most of the validation parameters like LOQ, Linearity range, Column and mobile phase used in different dosage forms as well as versatile techniques.

This review article provides a comprehensive evaluation of various analytical methods employed in the estimation of antifungal agents, particularly those used to treat Onychomycosis. Onychomycosis, a prevalent infection on nails caused by fungi, demands precise and accurate analytical techniques to ensure the safety and effectiveness of antifungal therapies. In this review, we discussed and compared a range of analytical technologies, highlighting their applications and sensitivity in the context of Onychomycosis drug analysis. This critical assessment aims to guide researchers and practitioners in selecting the most suitable methods for their specific analytical needs.

The aim of the study was to establish a GC-MS method for the determination of extractable substances in the stoppers of Ceftriaxone sodium bottles for injection, to establish an HPLC method for the determination of vulcanizing agent and antioxidant in Ceftriaxone sodium for injection bottle stopper and to analyze the correlation between the volatile substances of the rubber stopper and the clarity of solution.

GC-MS method was used with capillary column Restek rtx-5 (30.0 m×0.25 mm, 0.25 µm), the carrier gas was He at the flow rate of 1.8mL·min^-1, the column temperature was programmed temperature, and the scanning range was from29 to 600(m/z), and the volatile substances were using full scan. An inertsil ODS-3 column(250 mm×4.6 mm, 5 µm) was used for the HPLC analysis. The mobile phase A consisted of water containing 0.04% trifluoroacetic, and the mobile phase B consisted of acetonitrile containing 0.04% trifluoroacetic acid, the gradient elution was used, and the flow rate was set as 1.0 mL·min^-1.

Antioxidant BHT(264), silicone oil, and other organic compounds in the rubber stopper permeated and migrated to the sample with acceleration time by GC-MS. A good linearity was observed over the range of 0.5-100 μg·mL^-1(r>0.999). The detection limits of the vulcanizing agent and antioxidant were about 0.03 μg·mL^-1, and the quantitation limits were about 0.1 μg·mL^-1. The average recoveries (low, medium, and high) of antioxidants (168, 264, 330, 1076, 1010) and vulcanizing agents (carbon disulfide, sulfur) were between 90.0% and 110.0%, and the corresponding RSD were less than 5% (n=9) by adding standard recovery experiments. The stability test showed that the antioxidant and the vulcanizing agent solution had good stability and was stable within 24 hours.

The GC-MS/HPLC method can be used to control the quality of the rubber stopper of cefuroxime sodium for injection. The compatibility study and comprehensive evaluation system of Ceftriaxone sodium for injection packaging materials have been initially formed.

Radix astragali (a Tonic-Qi traditional Chinese medicine) can enhance cellular metabolism and increase the lifespan of cells. Spermidine can markedly extend the lifespan. On the basis of these considerations, we assumed whether any relationship existed between the anti-aging activity of Radix astragali and spermidine.

In this research, spermidine and 10 other kinds of biogenic amines in Radix astragali samples were identified and determined using high performance liquid chromatography-diode array detector (HPLC-DAD) with precolumn derivatization. Biogenic amines were extracted with hydrochloric acid, purified by n-butyl alcohol-dichloromethane extraction, and reacted with dansyl chloride for derivatization before HPLC analysis.

The method had good repeatability and reproducibility for the quantitative determination of biogenic amines in Radix astragali samples. Putrescine, spermidine, and spermine were detected in 10 batches of Radix astragali samples. The total biogenic amines concentration was 48.09±2.22 mg/kg. Spermidine (22.84±2.59 mg/kg) was the highest amine in Radix astragali samples, followed by putrescine and spermine. This is the first report that Radix astragali contains biogenic amines, especially high content spermidine.

The high content of spermidine might be the one reason for Radix astragali with Tonic-Qi and anti-aging effect.

Hispidulin, a flavonoid renowned for its diverse pharmacological activities, is abundant in S. barbata D. Don. Given its prevalence, it is essential to establish a dependable analytical method for quantifying hispidulin in this plant.

This study introduces a sensitive and reliable high-performance thin-layer chromatographic (HPTLC) method for both qualitative and quantitative analysis of hispidulin in S. barbata D. Don. Pre-coated TLC aluminum plates were utilized, and after testing various mobile phase combinations, the most effective separation was achieved with Toluene-ethyl acetate-formic acid (5:4:1, v/v/v). The method underwent extensive validation for linearity, specification, instrument precision, precision, limits of LOD and LOQ, accuracy, and robustness.

The developed method demonstrated excellent linearity over a specified concentration range, with a determination coefficient (r²) of 0.988. A well-defined spot at Rf 0.7, corresponding to hispidulin, was observed. The concentration of hispidulin in the hydroethanolic extract of S. barbata D. Don was quantified as 13.02 μg/mg of extract.

In conclusion, the HPTLC method presented in this study offers a simple, accurate, and robust tool for quantitatively analyzing hispidulin in the hydroethanol extract of S. barbata D. Don. This method is suitable for routine quality control and standardization of herbal formulations containing S. barbata D. Don, thereby contributing to the advancement of research in natural product-based pharmaceuticals.

Vitamin A and D deficiency in children is a common public health problem. In China, almost all children are administered vitamin A and D preparations daily and they should be consumed continuously until the age of 18. Children are sensitive to elemental impurities, including heavy metals. However, there are no regulatory requirements or reports on the risk assessment of elemental impurities in marketed vitamin A and D preparations.

The aim of this study was to propose an accurate and efficient method suitable for samples from different manufacturers to detect elemental impurities and conduct risk assessments according to the ICH Q3D guidelines.

We developed a universally applicable digestion method for capsules and an ICP–MS method for quantitative analysis of 28 elemental impurities in vitamin A and D formulations. These methods were validated according to the USP 233 guidelines. Elemental impurities in 15 batches of vitamin A and D products from 10 manufacturers and their capsule shells were determined, and risk assessment was conducted according to the International Council for Harmonization Q3D guidelines.

All elemental impurities of toxicological concern met the Q3D requirements. However, the concentrations of various elements, including those of lead (not detected to 4.1 µg/g), arsenic (not detected to 7 µg/g), aluminum (not detected to 888 µg/g), and palladium (not detected to 36 µg/g), varied markedly. Moreover, the lead content in one batch from one manufacturer exceeded the control threshold.

In this study, we successfully developed an effective digestion method for processing capsules containing samples from different sources and a sensitive ICP–MS method for quantitative determination of 28 elemental impurities in vitamin A and D preparations. ICP–MS should be implemented for the evaluation and control of elemental impurities in vitamin A and D preparations. This will ensure safe long-term vitamin A and D supplementation in children.

Atypical peaks were observed in capillary electrophoresis with sodium dodecyl sulfate (CE-SDS) during the development of therapeutic monoclonal IgG4 antibodies (mAb-X). Based on the previous literature reports, the atypical peak may be caused by various factors such as post-translational modifications (PTMs), method-induced artifacts, sample degradation and sequence variants. Due to the high complexity structure of mAbs and the limitations of CE-SDS, acquiring comprehensive profiling of atypical peaks has historically been challenging.

Here we developed a strategy utilizing complementary analytical methods to identify the cause of atypical peak.

This strategy includes optimizing reduced CE-SDS method to evaluate artifacts induced by the analytical method, excluding potential glycation modifications, and utilizing Liquid Chromatograph Mass Spectrometer (LC-MS) to characterize mAb-X.

Our study demonstrates that the atypical peaks of mAb-X are a mixture of method-induced artifacts and variants in the C-terminal extension sequence of the light chain.

Strategy for complementary analytical methods tools helps to identify the cause of unknown species and plays a key role in product and process characterization.

Purified human albumin fractionated from plasma has a complex matrix that imposes a lot of interference in quality control testing, particularly for impurities at trace level. In this study, a simple approach has been studied and validated for the quantification of aluminium content using Graphite Furnace Atomic Absorption Spectrometry (GF-AAS). As per international guidelines, the linearity, accuracy, precision, specificity, limit of detection, and quantification have been assessed.

The linearity of the analyte response was evaluated over the range of concentrations from 5µg/L to 45 µg/L, and the correlation coefficient obtained was greater than 0.99. The mean recovery obtained for the accuracy ranged from 102.29% to 106.81% at three concentration levels. The specificity/selectivity evaluated for possible interference from other metal ions and relative standard deviation for the high and low content was 10.24% and 6.50%, respectively, which was statistically verified and not significant. Method precision was evaluated for repeatability and intermediate precision, and the relative standard deviation obtained was 1.83% and 4.61%, respectively. The limit of detection and quantification obtained was 1.30 µg/L and 4.10 µg/L, respectively.

Results obtained for the method performance show the suitability of the method for aluminium estimation in human albumin samples and should be used to control the limit of aluminium in human albumin blood products.

Conventional chromatographic techniques and direct analysis pose challenges in detecting certain potential genotoxic impurities, primarily due to factors such as the absence of a chromophore, low molecular weight, and insufficient chromatographic retention caused by high polarity. One such compound, N, O-Dimethyl Hydroxylamine, is of particular concern due to its structural similarity to Hydroxylamine, a recognized genotoxic impurity.

In response to this challenge, this article proposes a rapid derivatization approach utilizing Dansyl Chloride, coupled with Liquid Chromatography-Mass Spectrometry (LC-MS) for the detection of the derivatized product in the investigational drug substance. To preserve confidentiality, the specific name and structure of the drug substance have not been disclosed.

The developed method exhibits a reliable range of detection spanning from 5 ppm to 60 ppm with respect to a nominal drug substance concentration of 10 mg/mL. Throughout the method validation process, it demonstrated specificity, sensitivity, linearity, accuracy, and repeatability.

This methodology presents a versatile solution applicable in scenarios where N, O-Dimethyl Hydroxylamine serves as a reagent in the synthesis process of drug substances.

Aqueous solubility is a key parameter in understanding drug transport in the body and also in the development of analytical methods. Determination of a complete pH-solubility profile is essential during the pre-formulation stage, and it is also required to define the class of drug according to the biopharmaceutical classification system.

This study aimed to generate solubility data to obtain a complete pH-solubility profile for Atorvastatin calcium using the spectrophotometric method and to develop models for the prediction of aqueous solubility of Atorvastatin calcium at a given combination of the pH and temperature.

The developed pH independent spectrophotometric method was applied to determine the pH solubility profile of the drug at three different temperatures. Models for the prediction of solubility were generated by using a full factorial design and validated by determining solubility experimentally at some combinations of pH and temperature within the design spaces.

Solubility of Atorvastatin calcium was found to increase gradually with pH within a range of pH 1.2-4.0 and pH 9.0-12.0 while increasing drastically with pH within a range of pH 4.0-9.0 at all three temperatures. Experimental values of solubility of Atorvastatin calcium were found to be in good agreement with predicted values from models.

Predictive models generated from the experimental values are good indicative of the solubility of Atorvastatin calcium with respect to temperature and pH of the medium and can be used for accurate prediction of aqueous solubility within the design space of the models.

A simple, rapid and precise reverse phase–High performance liquid chromatography (RP-HPLC) method was developed for the determination of degradation impurity i.e. Oxidised follitropin in recombinant Follicle Stimulating Hormone (rFSH) Injection.

Chromatographic separation was performed using a C4 column of size: 250 × 4.6 mm, 5 µm along with C3 Guard Column (SB-C3 size: 125 mm x 4.6 mm, 5 µm) and using gradient elution. The flow rate was kept at 1.0 ml per minute and the detection wavelength was at 210 nm. The retention time of oxidised follitropin was ~14 to 15 minutes. The detector showed a linear response between the range of 2.46–63.325 μg/ml (5% - 125%) with a correlation coefficient value of 0.9987. After establishing the procedure, it was ensured for its intended usage by validation of the analytical parameters like specificity, linearity, accuracy, repeatability, and robustness as per the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) [Q2 (R1) Validation of Analytical Procedures: Text and Methodology].

All of the parameters performed using the current method yielded results that met the acceptance requirements. The detector showed a linear response between the range of 2.46–63.325 μg/ml (5% - 125%) with a correlation coefficient value of 0.9987.

As a result, a newly designed RP-HPLC method was capable of effectively separating impurities while maintaining acceptable limits.

A novel stability indicating RP-HPLC method was developed and validated for the simultaneous estimation of Pregabalin and Duloxetine by using the QBD approach.

To determine the optimal parameters for the duloxetine and pregabalin study, we used Design Expert version 13.0 in this work. The mobile phase consisted of 0.8 ml/min of methanol: water (80:20, v/v) with o-phosphoric acid-adjusted pH 3.A 250 mm × 4.6 mm ID, 5 µm particle size Cosmosil C18 column was used. The UV-3000-M detector was used to detect at 218 nm.

Duloxetine's retention time was 7.153 ± 0.1 min, whereas Pregabalin's was 4.481±0.1 min. The ICH parameters like linearity, accuracy, robustness, ruggedness, LOD and LOQ, and system suitability were determined. Likewise, the tailing factors were found to be 1.27 and 1.26, while the theoretical plates of duloxetine and pregabalin were found to be 8313 and 8549, respectively. The recovery study shows the results (99.37–99.84% for pregabalin and 99.03–99.74% for duloxetine), and the precision was obtained with a %RSD of less than 2%. The result of the assay was 99.92% for pregabalin and 99.39% for duloxetine. The developed method was used for the forced degradation study. The Box-Behnken design experiment using Design Expert 13.0 was adopted for the QBD approach.

All the values obtained for different parameters were within the acceptable range of ICH. The developed method can be routinely used for the simultaneous estimation of Pregabalin and Duloxetine by using the QBD approach.

Lipopolysaccharide (LPS) is an essential constituent of the outer membrane of gram-negative bacteria, such as Salmonella typhimurium, and it plays a crucial role by inducing disease in the host. Penicillin-binding protein 1B (LpoB) is a key enzyme in the production of peptidoglycans, making it a potential target for the development of new antimicrobials. Flavonoids are naturally occurring plant-derived chemicals with a wide range of pharmacological properties, including antibacterial capabilities. The goal of this study was to identify the potential flavonoid that inhibits the protein LpoB using computational approaches and compare it with the standard antibiotic ciprofloxacin.

The study was carried out by selecting fifty flavonoids based on Lipinski’s rule of five. Molecular docking was carried out for selected flavonoids and ciprofloxacin against the LpoB protein using AutoDock 4. A 100 nanosecond molecular dynamic simulation was performed for apoprotein, LpoB-fisetin, and LpoB-ciprofloxacin complexes, followed by free energy calculation by Molecular Mechanics Generalized Born Surface Area (MMGBSA) solvation analysis.

The docking results revealed that fisetin displayed five hydrogen bonds with a binding affinity of -4.67 kcal/mol, and ciprofloxacin exhibited a binding affinity of -4.36 kcal/mol with two hydrogen bonds. The apoprotein and fisetin complex remained stable throughout the 100 ns molecular dynamic simulation, while the ciprofloxacin complex lost its stability. The MMGBSA analysis with fisetin showed better binding free energy compared to ciprofloxacin.

The present study has emphasized the potential of flavonoids as probable candidates that can inhibit the protein LpoB. The integration of molecular docking, dynamic simulations, and MMGBSA analysis has provided significant insight into the thermodynamics and binding interactions of the LpoB- fisetin complex, and it has enabled further experimental validations.

Oxaliplatin, a platinum-based antineoplastic agent, is widely used to treat colorectal cancer. It is well-known for its capacity to hinder the development and division of cells, especially fast-dividing ones, like cancer cells, via the creation of DNA adduct. The currently published oxaliplatin analytical methods require a complex, difficult-to-understand procedure, and are costly.

The main objectives of our study were to select the chromatographic parameters, develop a UFLC method and validate it, and validate the results according to ICH guidelines.

In this UFLC study, a normal phase C18 column (250cm x 4.6 mm x5 µm) with a mobile phase containing 0.01 M orthophosphoric acid and acetonitrile (95:5 V/V) has been used at pH 3.5. Flowrate has been fixed at 1ml/min and the sample has been tested in the UV range for detection. The methods have been validated for precision, linearity, forced degradation studies, robustness, and accuracy.

The retention time of the drug has been found to be >8min. The calibration curve of the drug has been obtained within the range of 10–240 µg/ml. The results of this analysis have been validated according to ICH guideline Q2 (R1) for registration of human use.

The UFLC method we have used for oxaliplatin quantification has been found to be simpler, easier to understand, and more cost-effective than standard HPLC as it has consumed less mobile phase and less time. Thus, we can conclude that this new, simple, and easy method may be a useful alternative to the existing standard methods for oxaliplatin.

A novel chemosensor has been developed utilizing a newly synthesized pyridine-carboxaldehyde thiosemicarbazone silver nanoprobe (PT-AgNP) for detecting and quantifying iodide ions in aqueous media, both visually and spectrophotometrically using a UV-Vis spectrophotometer.

Notably, this sensor demonstrates remarkable selectivity for I- ions, effectively distinguishing them from other common anions such as AcO^-, Br^-, Cl^-, CN^-, and F^-. The PT-AgNP solution undergoes a rapid color change from yellow to black, providing a clear visual indication of the presence of iodide ions. This color transition is directly proportional to the concentration of iodide ions, as indicated by the reduction in the intensity of the surface plasmon resonance band due to nanoparticle aggregation. A linear correlation is observed between the change in intensity and the concentration of iodide ions within the range of 10 to 50 nM, with a detection limit of 8.8 nM. The stability of the PT-AgNP complex is evaluated through experimental methods such as UV-Vis spectroscopy, zeta potential analysis, and powder X-ray diffraction (PXRD), complemented by theoretical calculations using density functional theory (DFT) with Gaussian 09W software.

Theoretical investigations reveal that the silver ion (Ag⁺) and the imine bond of pyridine carboxaldehyde act as potential nucleophilic targets, consistent with the observed morphological color change from yellow to black upon PT-AgNP complexation with iodide ions.

Furthermore, DFT calculations indicate a higher HOMO-LUMO energy gap in the pyridine molecule compared to the PT-AgNP complex, suggesting its enhanced sensitivity and reactivity towards iodide ions.

Mangiferin shows great promise as a potent drug for a wide variety of diseases. Its low bioavailability and poor water solubility, however, restrict its therapeutic use.

The aim of the study goal was to systematically design a UV-spectroscopy method for mangiferin quantification in analytical samples that is quick, easy, and very sensitive. In order to validate the method, UV spectroscopy was used to check for specificity, accuracy, precision, and linearity. The models were constructed with Design Expert^Ⓡ V.10 and optimised using Box-Behnken Design (BBD), a three-factor and three-level procedure.

The devised method demonstrated good levels of sensitivity, specificity, accuracy, and precision, according to the results. The absorbance and concentration showed a strong linear relationship in the given 5-25 μg/ml range for several wavelengths, with correlation coefficients of 0.989, 0.982, 0.905, and 0.896 at 364.5, 370, 378, and 265nm, respectively. The intraday precision was 0.788 at 364.5 nm, 0.801 at 370 nm, 0.739 at 378 nm, and 0.721 at 256 nm for the concentration of 20 μg/ml. Particle size and entrapment efficiency, two dependent variables in the microspheres formulation, were best suited by the models derived when the observed responses were fitted to the design. Microspheres had a high entrapment efficiency and were microsized. Interestingly, drug-encapsulated microspheres containing mangiferin maintained the spherical shape.

The existence of well-resolved peaks and good recovery of mangiferin in the analytical method for analysis makes it ideal and acceptable for further use.

Triamterene is a potassium-conserving diuretic mainly used in the treatment of edematous diseases. Although there are some methods to measure the content of triamterene, the existing methods have the characteristics of sample destructiveness and low flux, making it difficult to meet the needs of online monitoring. In recent years, transmission Raman spectroscopy (TRS), as a new technology for the determination of drug content, has emerged as being non-destructive and rapid and provides a new method for the determination of triamterene content.

In this study, we used transmission Raman spectroscopy combined with partial least squares (PLS) approaches to establish a six concentration levels model for measuring the content of triamterene. The model was applied to determine whether tablets are commercially available.

Firstly, TRS was used to collect the spectra of the principal components and mixed excipients of triamterene, and the feasibility test was carried out. Secondly, six concentration levels were determined by the design of experimental (DOE), and hand-made tablets were prepared to obtain corresponding spectra. The content prediction model was established by the PLS method, and the content of triamterene was determined by high-performance liquid chromatography (HPLC) to correct the model. Finally, the model was applied to the determination of triamterene in commercially available tablets.

The results showed that the established model was successfully applied to the determination of triamterene. The values of RMSEC (0.0089783) and RMSECV (0.0097241) of the final model were very low and close to each other. The relative error of 12 hand-made tablets predicted by this model was less than 5% compared with the results determined by HPLC. In addition, in the process of applying the model to the determination of the content of commercially available tablets, the accuracy of the model can be significantly improved by adding the spectrum of commercially available tablets. The corrected model was used to determine the content of triamterene in two commercially available tablets. The results showed that the relative error was less than 5%.

We described a new strategy to analyze the content of active pharmaceutical ingredients (API) in triamterene tablets by TRS with PLS. The established model has the advantage of non-destructive and rapid quantitation, which can provide a new method for real-time monitoring of production lines and promote the development of process analytical technology (PAT).

Cordyceps sinensis, a renowned traditional Chinese medicinal substance, contains pharmacologically beneficial compounds, including γ-aminobutyric acid (GABA), necessitating efficient analytical methods for quality assessment. This study aims to develop a rapid, cost-effective, and eco-friendly liquid chromatography-tandem mass spectrometry (LC–MS/MS) method for GABA quantification in Cordyceps sinensis and its related species. The objective is to enhance the quality control standards within the Cordyceps sinensis industry and for those of its related species.

The study innovated a swift analytical procedure. Optimal conditions were determined through systematic evaluations of extraction solvents, durations, and chromatographic settings, prioritizing speed and solvent minimization.

The proposed LC–MS/MS method achieved precise quantification of GABA in a reduced time frame and significantly lowered solvent consumption, enhancing method efficiency by 22-fold compared to reported LC methods. The method exhibited robustness and scored the highest blue applicability grade index score, underscoring its suitability for academic and industrial applicaition.

The validated LC–MS/MS approach offers a sustainable avenue for the rapid and accurate measurement of GABA in Cordyceps sinensis and its related species, improving the quality control process and ensuring product authenticity. This method stands out as a model for green analytical chemistry, propelling forward the eco-friendly analytical evaluation of health-related compounds.

The objective of the present work is to develop and validate a novel, specific, precise, and reliable method for the estimation of Calotropis gigantea in bulk and herbal dosage form using the RP-HPLC method.

RP-HPLC analysis was performed using a C18 column of dimension 150×4.6mm, 5 µ. The chromatography system comprised an Agilent 1220 Infinity II LC equipped with a VWD detector and a 1220 Infinity II LC binary pump, wherein the instrument operation was managed through Control Panel software at a flow rate of 0.5 ml/min. Methanol: water in the ratio of 55:45 was used as the mobile phase, and the effluents were analyzed at 275nm. The proposed method was validated for various parameters like linearity, precision, accuracy, robustness, ruggedness, selectivity, limit of detection, limit of quantification, and assay as per the ICH Q2(R1) guidelines.

Linearity was noted over a concentration range of 50-250 µg/ml with a correlation coefficient of 0.999. The limit of detection (LOD) and limit of quantification (LOQ) were determined to be 16.02 and 48.56 µg/mL, respectively. The % RSD for interday and intraday precision studies was less than 2%, which was within the official RSD limit. Recovery analysis performed using marketed formulation was found to be in the range of 97-105%.

The method developed was validated according to the ICH guidelines. Hence, it is evident that the developed method is novel, sensitive, precise, and reliable, and it can be successfully applied to estimate Calotropis gigantea in bulk material and its herbal dosage form.

The in-vitro release test (IVRT) is a tool to measure the amount and the release rate of active pharmaceutical compounds released from topical semisolid dosage forms. The IVRT provides significant information for product performance assessment and evaluation. It is also used to assess the bioequivalence study (biowaivers) for topical semisolid products.

The study aims to develop and validate the IVRT method for qualitative and quantitative estimation of ganciclovir topical products and to demonstrate the similarity between the marketed reference product and the in-house test product of ganciclovir ophthalmic gel.

The method was developed using a vertical diffusion cell with a synthetic cellulose membrane, simulated tear fluid as the receiver media, and UV detection. The IVRT study was performed at 100rpm and 32℃ for 6hr. The marketed formulation containing 0.15%w/w ganciclovir was used as a reference.

The in-house test product of ganciclovir met all characterization criteria. The analytical method was optimized and validated with a concentration range of 2-14μg/ml and a regression coefficient of 0.9997 as per the ICH guideline. The developed IVRT method was simple, economical, linear, robust, reproducible, sensitive, specific, and selective to evaluate the drug release from the formulation. The %recovery at 6hr was found to be 84.43% and 78.68% for reference and test product of ganciclovir ophthalmic gel with correlation coefficient R² 0.9947 and 0.9921, respectively, this value justified the biowaivers between the reference and test formulation.

This method can be utilized to check topical semisolid product quality, product performance, and product uniformity. Additionally, it can also be used to waive the requirement for bioequivalency studies for ganciclovir ophthalmic gel.

N-nitrosamines have recently been discovered in metformin hydrochloride and other generic drugs. To quantify the five N-nitrosamines in metformin hydrochloride, we devised sensitive and reliable multiple reactions monitoring mode-based GC-MS/MS technique, particularly, N-nitrosodiethy amine (NDEA), N-nitroso ethyl isopropylamine (NEIPA), N-nitrosodiisopropylamine (NDIPA), N-nitrosodipropylamine (NDPA), as well as N-nitrosodibutylamine (NDBA).

To develop a sensitive, precise, and accurate MRM mode based GC-MS/MS method for the quantification of five N-nitrosamines in metformin hydrochloride and valídate as per ICH guidelines.

The settings for mass spectrometry and gas chromatography were optimized. With the linearity, sensitivity, specificity, accuracy, and precision of the parameter, the procedure was as per the recommendation of ICH: International Council for Harmonization guidelines.

N-nitrosamines in metformin hydrochloride had detection and quantification limits of 0.001 ppm and 0.004 ppm, correspondingly. The obtained results were within the sensitivity limitations issued by the US Food and Drug Administration. The calibration curve's regression coefficients for five N-nitrosamines were over 0.99, demonstrating the process's good linearity. The retrievals of N-nitrosamines in metformin hydrochloride between 97.1 – 127.4%. The RSD (Relative Standard Deviation) was lower than 10% for both inter-day and intra-day precision studies.

The proposed method exhibited a rapid analysis capability, high accuracy, sensitivity, and precision, making it a trustworthy method for monitoring N-nitrosamines in metformin hydrochloride.