Chromatographic Method Research Articles

Evaluation of the Greenness, Whiteness, and blueness profiles of stability indicating HPLC method for determination of Denaverine hydrochloride and benzyl alcohol in pharmaceuticals

Recently, there has been important emphasis in pharmaceutical analysis on the stability of drug formulations and the development of appropriate stability-indicating studies. In this regard, a comprehensive stability-illustrating RP-HPLC approach has been established and validated for the assay of denaverine hydrochloride (DEN) and benzyl alcohol (BNZ) in Sensiblex® Injectable Solution.Different stress conditions were applied to both components, following the guidelines of the International Conference on Harmonization (ICH). Using the isocratic elution technique, DEN, BNZ, and their degradation products were effectively isolated and quantified on an Inertsil C8 column at room temperature. The mobile phase consisted of acetonitrile: water: orthophosphoric acid (80:20:0.1, by volume), and the flow speed was maintained at 0.8 mL/min. Detection was performed at 220 nm using a diode array detector, with concentration ranges of 10.00–30.00 and 5.00–15.00 μg/mL for DEN and BNZ, respectively. The total analysis time was less than five minutes, establishing this novel chromatographic method as a priority for routine quality control analysis of both drugs. The inclusion of acetonitrile was necessary for achieving adequate resolution. The environmental impact was evaluated using three approaches: Green Analytical Procedure Index (GAPI), Analytical Eco-Scale, and Analytical GREEnness metric (AGREE). Additionally, White Analytical Chemistry (WAC) was employed to evaluate the quality (R), ecological impact (G), and economic viability (B) of the developed approach.Additionally, the newly presented Blue Applicability Grade Index (BAGI) metric was also assessed. The final Eco-scale score of 85 and the AGREE score of 0.65 indicate the environmentally friendly nature of the new chromatographic method. The BAGI final score was 82.5, while the overall score of the WAC tool was 91.8, highlighting the method's practicality and utility. DEN exhibits the highest degradation (24%) in acidic conditions, whereas BNZ is particularly susceptible to oxidative degradation, with a degradation percentage of 35%. New four degradation products were formed, and the two investigated compounds were efficiently separated and analyzed in their presence. Further identification of degradation products for DEN and BNZ is strongly recommended, employing a mass spectrophotometric detector. Notably, the novel method is accurate, reliable, economical, and time-efficient. In conclusion, it can be effectively employed for routine quality control and stability assessment of DEN and BNZ in both their pure form and pharmaceutical formulations.

Simultaneous quantification of terpenes and cannabinoids by reversed-phase LC-APCI-MS/MS in Cannabis sativa L. samples combined with a subsequent chemometric analysis.

Cannabis sativa L. has been the most discussed medicinal plant in recent years. In particular, the dynamic shift from a formerly illicit and tightly controlled substance to a plant recognized for both medicinal and recreational purposes has brought C. sativa into the global spotlight. Due to the ongoing international legalization processes, fast and convenient analytical methods for the quality control of C. sativa flowers for medicinal and recreational purposes are of tremendous interest. In this study, we report the development and validation of a liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based method applying atmospheric pressure chemical ionization (APCI) to fully quantify 16 terpenes and 7 cannabinoids including their acidic forms by a single chromatographic method. The method presented here is unique and simple, as it eliminates the need for derivatization reactions and includes the unconventional analysis of volatile compounds by liquid chromatography. Samples were prepared by a simple and fast ethanolic extraction. Separation was accomplished within 25min on a reversed-phase C18 column. Method validation was conducted according to international guidelines regarding selectivity, accuracy, precision, robustness, and linearity. Detection was done in multiple reaction monitoring, which allowed the simultaneous quantification of co-eluting analytes applying two selective mass transitions. In addition, due to reproducible in-source decarboxylation, the acidic forms of cannabinoids were reliably quantified using mass transitions of the neutral forms. The accuracy given as the bias was below 15% for all analytes. Matrix effects for cannabinoids were studied by spiking Humulus lupulus extracts with the analytes at varying concentrations. APCI did not show susceptibility toward ion suppression or enhancement. In addition, the recovery effect after spiking was between 80 and 120% for terpenes. Further, 55 authentic C. sativa extracts were fully quantified, and the obtained results for the terpene profiles were compared to state-of-the-art gas chromatography coupled to flame ionization detection. Comparable results were achieved, emphasizing the method's applicability for cannabinoids and terpenes. Further, acquired metabolite patterns for C. sativa samples were studied, identifying a relationship between cannabinoid and terpene patterns, as well as the abundance of myrcene in CBD-dominant C. sativa strains.

Current analytical methods and applications used in the insight of serum proteins interactions with various food additives, pesticides, and contaminants

In recent years, many societies have expressed increasing apprehension regarding the potential negative impacts of food additives, pesticides, and environmental contaminants on human health. Environmental or occupational exposure to these compounds can cause significant adverse effects on human health by causing temporary or permanent changes in the immune system. There is supporting evidence linking pesticides/food ingredients/contaminants-induced immune alterations to the prevalence of diseases associated with changes in immune responses. Hence, it is essential to comprehensively understand the key mechanisms contributing to immune dysregulation induced by these substances, including direct immunotoxicity, endocrine disruption, and antigenicity. The impact of pesticides/food ingredients and contaminants on the human body ranges from mild to severe, depending on their affinity for blood components. These compounds form complexes with blood serum proteins, influencing their metabolism, transport, absorption, and overall toxicity. Numerous studies in the literature have explored the interactions between serum proteins and various molecules, including pesticides, drugs, and food dyes. These investigations employed a range of techniques, including spectroscopy, electrochemical and chromatographic methods as well as molecular modeling and molecular dynamics simulations analyses. This recent review, spanning from 2020 to the present, has been employed to investigate the binding characteristics, mechanisms, and attributes of different food additives, pesticides, and contaminants with serum proteins by using various techniques such as steady-state fluorescence, circular dichroism and ultra-violet spectroscopies, and computational docking methods. The review provides insights into these compounds’ positions and affinities to proteins and possible effects on human health through detailed research studies.

Oak Leaves as a Raw Material for the Production of Alcoholic Fermented Beverages

This study aimed to point out the possible use of oak leaves (Q. petraea) in the production of fermented alcoholic beverages. Parameters such as antioxidant capacity, total phenolic content, phenolics and sugars were determined using spectrophotometric and chromatographic methods. pH values were also determined, and in the final product with a fermentation length of 85 days, the alcohol content was determined and sensory analysis performed. The antioxidant capacity of the beverage was lower compared to the infusions before fermentation, and its highest values were recorded in the leaf samples, in which the highest values of phenolic compounds and the total phenolic content were also recorded. A decrease in the content of total phenolics was recorded with the increasing length of fermentation in beverage samples. However, the fermentation process had a positive effect on the contents of some phenolic substances such as catechin, gallic acid and gallocatechin. Sensory analysis showed a higher acceptability of the fermented beverage without the addition of orange, which could be caused by the higher sugar content in these samples. Oak leaves therefore represent a suitable raw material for the production of a fermented alcoholic beverage, without the need to enrich the taste with other ingredients.

Stability of Bioactive Compounds and Antioxidant Activity in Rosehip Juice (Rosa spp.)

Rosehip fruits, characterized by their high concentrations of bioactive compounds and antioxidant activity (AA), have been traditionally used to make jams, infusions, and juices. Thus, the objective of this research was to evaluate the stability of rosehip juice by determining the concentrations of bioactive compounds and total phenols and the AA using chromatographic and spectroscopic methods. The stability of the juice was evaluated with three treatments and different storage conditions, namely, unpasteurized–refrigerated, pasteurized–room temperature, and pasteurized–refrigerated, and measurements were taken for eight months. Individual and total phenolic compounds, evaluated by chromatographic methods, reported differences until the end of this study. The total phenolic compounds by Folin–Ciocalteu method presented an average decrease of 57% in the three treatments in relation to the initial conditions. On the other hand, the ascorbic acid content decreased considerably, disappearing at week six. Furthermore, for the unpasteurized–refrigerated and pasteurized–refrigerated samples, a correlation was found between flavonols, total phenols, ascorbic acid, and antioxidant activity determined by the TEAC method. For the pasteurized–room temperature samples, correlations were found between the levels of several flavonols, hydroxycinnamic acid, total phenols, and ascorbic acid and the antioxidant activity determined by the CUPRAC method. The stability of the compounds was mainly correlated with the storage conditions of the juice and not with pasteurization. The highest stability was observed for the unpasteurized–refrigerated and pasteurized–refrigerated samples. Although the concentrations of the compounds evaluated decreased during this study, significant levels of AA persisted, providing beneficial characteristics for consumer health.

Contamination and pesticide multiresidue analysis in cotton production systems in Benin

High quantity of chemical pesticides spraying in conventional cotton production systems may affect negatively natural ecosystems components. This study examined the contamination levels of soil in Benin's cotton production system in West Africa by residues of pesticides used in cotton farming. One hundred and fourteen soil samples from six conventional and organic cotton production systems were collected and analysed. Multi-class pesticide residues were extracted from the soil samples, and analysed using respectively modified QuEChERS extraction and LC–MS/MS chromatography methods. Results showed an overall soil contamination to emamectin benzoate (18.5 μg/kg), imidacloprid (116.3 μg/kg), profenofos (12.7 μg/kg), acetamiprid (10.8 μg/kg), triasophos (12.6 μg/kg), abamectin (14.3 μg/kg), and deltamethrin (10.4 μg/kg). Especially, emamectin benzoate was detected with a high contamination in Banikoara district (18.5 μg/kg). Nevertheless, these contaminations were not deemed threatening from a toxicological perspective. Soils in conventional cotton cultivation displayed lower organic matter levels but higher concentrations of pesticides, whereas soils in organic cotton cultivation were less degraded and contaminated. Consequently, it is imperative to conduct environmental risk assessments and monitor key pesticide metabolites to establish sustainable cotton production systems in Benin.

Development and validation of stability indicating ultra‐high‐performance liquid chromatographic method for assay and impurities of mexiletine hydrochloride and mexiletine hydrochloride capsules

AbstractMexiletine (MEX) is an antiarrhythmic drug used to treat acute and chronic ventricular arrhythmias. A simple isocratic, rapid, specific, stability‐indicating, and sensitive reverse‐phase ultra‐high‐performance liquid chromatography (UHPLC) method was developed and successfully validated to quantify the assay and impurities of MEX hydrochloride. The new UHPLC method showed the optimum separation of MEX and its seven impurities in 20 min by using sodium acetate buffer (0.14 mM) with 0.3% of glacial acetic acid (pH 4.8) and methanol in the ratio of 40:60 (v/v) as mobile phase. The method used an Acquity HSS T3 (100 × 3.0 mm, 1.8 µm) chromatographic column at a 0.2 mL/min flow rate. The injection volume is 2 µL, and 254 nm is the detection wavelength. Note that, 25°C is the column oven temperature. The method is linear over the concentration range of the quantification limit (0.03%) to 150% (0.3%) of the specification level (0.2%) for the impurities and 50%–150% for the assay method. The quality control lab of bulk drugs and finished dosage form successfully applied the new UHPLC method for quantification of assay and impurities of MEX hydrochloride.

STABILITY BASED HPLC METHOD FOR CYCLOPHOSPHAMIDE RELATED SUBSTANCES IN FINISHED DRUG PRODUCTS: DEVELOPMENT AND VALIDATION

Objective: The current study aimed to develop a simple, sensitive, and precise high-performance liquid chromatographic (HPLC) method for estimating cyclophosphamide and its related substances, as well as to implement the developed method in a capsule product. Methods: Method development was performed using various solvent and buffer-solvent ratios at different flow rates for better resolution and to decrease the run time. The developed method was validated in accordance with the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) guidelines. The developed method was implemented to estimate the amount of cyclophosphamide and its related substances. Results: Chromatographical conditions were optimised, and the best chromatographical conditions with adequate resolution for cyclophosphamide and its related substances were achieved using the enable X-Bridge C18 column, using a mobile phase combination of phosphate buffer pH 7.0, water, methanol, and acetonitrile at a flow rate of 0.5 ml/min. The detection was monitored at a wavelength of 200 nm. The developed method was validated for system suitability, specificity, limit of detection (LOD), limit of quantitation (LOQ), linearity, precision, accuracy and robustness. The results indicate that the method was sensitive and could detect and quantify lower levels of cyclophosphamide and its related substances. The linearity range was from LOQ to 150 %, and a correlation coefficient ranging from 0.9987 to 0.9999 indicates that at this concentration range, substances were highly linear. This was further supported by satisfactory forced degradation studies. Conclusion: The developed analytical method is simple, precise, and reproducible and thus can be used for the stability-indicating analysis of cyclophosphamide and its related substances in pharmaceutical formulations.

Development and Validation of a RP-HPLC Method for the Simultaneous Determination of Silver Sulfadiazine and Sodium Hyaluronate in the Presence of Methyl and Propyl Paraben in a Pharmaceutical Cream for Burns.

A direct and precise isocratic RP-HPLC method for simultaneous determination of silver sulfadiazine (SSD) and sodium hyaluronate (SH) in the presence of methyl (MP) and propyl parabens (PP) was developed and validated. Agilent chromatograph with X-Select C18 column (250 × 4.6mm2, 5μm) was used. Chromatographic separation was achieved using a mobile phase consisting of acetonitrile and 0.05M phosphate buffer (pH5.0 to which added triethyl amine 0.5ml/L), at a ratio 35: 65v/v. Elution was used at flow rate of 1.0mL/min at ambient temperature with UV detection at 205nm. The retention times for SH, SSD, MP and PP were 1.49, 3.3, 6.7 and 19.5min, respectively. The presented chromatographic method was fully validated in accordance with ICH requirements, it was valid over linearity ranges of (0.80-100.00μg/mL) and (3.20-100.00μg/mL) for SSD and SH, respectively. Acceptable precision and accuracy were obtained for concentrations over the standard curve ranges and the sensitivity of the method, as the limits of detection and quantification for each active ingredient was also determined. The validated method was successfully applied for the quantification of SSD and SH in pharmaceutical cream formulation and the mean recovery %±SD were 100.93 ± 0.985 and 100.05 ± 0.668 for SSD and SH; respectively, indicating satisfactory accuracy of the method.

Chromatographic methods and approaches for bioequivalence study, drug screening and enantioseparation of indapamide

AbstractIndapamide (Indp) and certain other diuretics have been abused in sports, therefore, having sensitive methods for its detection and assay in biological fluids (whole blood, plasma, serum, and urine) is of significant importance. The racemic mixture of Indp is being used as an active pharmaceutical ingredient among other commonly prescribed diuretics. The regulatory authorities and pharmaceutical industries demand analytical methods for successful enantioseparation of such molecules. The paper presents a critical overview of the scientific issues of the application of contemporary techniques involving various chromatographic approaches (with liquid or supercritical fluid as mobile phases) and capillary electrophoresis and method development, for drug screening, assay, bioequivalence studies and enantioseparation of indapamide with their results. It also covers the historical developments that led to significant breakthroughs in research and concise evaluations of research in the area.Different types of chromatographic methods (HPLC, CEC, SFC etc) discussed herein provide an insight and a choice to select a method to (i) screen Indp for drug abuse, (ii) separate, isolate and quantify the enantiomers of Indp and (iii) investigate their pharmacokinetics as markedly different species and not as a total drug. The article evaluates the field's status with a broad base and practical oriented approach so that the underlying principles are easily understood to help chemists and non-specialists gain useful insights into the field outside their specialization and provide experts with summaries of key developments. To the best of authors' knowledge there has been no attempt to review such methods for analysis of Indp and this is the first report of its kind.

Isolation and characterization of major degradants in dihydroergotamine injection

AbstractIn this study, we report the systematic approach for characterization of two major degradant impurities, which are not listed in any compendia and were formed during the stability studies of Dihydroergotamine mesylate injection (DHE). An ion-pair UPLC chromatographic method was developed to quantify the related substances present in the DHE injection drug product. The same was used to monitor the impurity profiling during its stability. The two unknown impurities were observed at RRT about 0.08 (Impurity-1) and RRT about 0.80 (Impurity-5) and found to be significantly increasing on stability. Forced degradation studies revealed the nature of the impurity and conditions required for enriching them. A Mass compatible HPLC method was developed to quantify only these two impurities using 25% ammonia and formic acid in water. Their mass numbers were identified using LC MS/MS with triple quadruple mass spectrometer coupled with a HPLC. These two impurities were then isolated from enriched products using preparative HPLC. These impurities were then characterized using Mass and NMR analysis along with Q-TOF elemental analysis.

Sensitive and validated UPLC-MS/MS method for the identification and characterization of forced degradation products for felodipine

AbstractA rapid, stability indicating reverse phase liquid chromatographic method was developed for the determination of purity of Felodipine in active pharmaceutical substance form in the presence of its impurity and its degradation products. To develop the method which is also compatible to liquid chromatographic mass spectroscopic technique. The developed method is also used to determine the assay of Felodipine in bulk drug form. The drug is subjected to various stress conditions like acidic, basic, oxidation, UV light and thermal conditions. Considerable degradation was observed during base hydrolysis. Two degradation products were identified. The Waters Acquity UPLC BEH C18, 2.1 × 100 mm, 1.7 µm Column was used to achieve chromatographic separation. The gradient conditions, diluent and injection volume were optimized to achieve the acceptable resolution between impurities and its degradation products from Felodipine and to get good peak shapes. The masses were determined for main compound and its identified degradation products. Further, the characterization studies for main compound and its degradation products were performed using LCMSMS Q-TOF.

Stability-Indicating HPLC Method for Determination of Ibuprofen and Famotidine Degradation Products.

A new stability-indicating high-performance liquid chromatographic method for the quantitative determination of ibuprofen and famotidine degradation products in combined pharmaceutical products was developed and validated. The current aim of this study is to develop a rapid, accurate and robust analytical stability indicating impurity method that can separate ibuprofen, famotidine and their related impurities by using a reversed-phase high-performance liquid chromatography. A Zorbax SB-Phenyl column (4.6 × 150mm2, 5-μm particle size) with mobile phase containing phosphate buffer solution with a pH value of 3.0 and acetonitrile was used. The flow rate was 0.8mL/min and the analytes were detected by UV detector at 265nm. The retention times of ibuprofen and famotidine were 18.43 and 5.14min, respectively. This method was validated to confirm specificity, linearity, sensitivity (limit of detection and limit of quantitation), precision, accuracy, robustness and sample stability according to the International Conference on Harmonization guidelines. Studies have been completed and reported with two active substances in the combined dosage form and seven impurities in total. There is no method in the literature that simultaneously distinguishes and quantitatively analyzes both active substances and degradation products.

Rapid and simultaneous determination of curcuminoids and gingerols in food products containing turmeric and ginger using paper spray mass spectrometry.

Turmeric and ginger are extensively employed as functional ingredients due to their high content of curcuminoids and gingerols, considered the key bioactive compounds found in these roots. In this study, we present an innovative and fast method for the assay of curcuminoids and gingerols in different foods containing the two spices, with the aim of monitoring the quality of products from a nutraceutical perspective. The proposed approach is based on paper spray tandem mass spectrometry coupled with the use of a labeled internal standard, which has permitted to achieve the best results in terms of specificity and accuracy. All the calculated analytical parameters were satisfactory; accuracy values are around 100% for all spiked samples and the precision data result lower than 15%. The protocol was applied to several real samples, and to demonstrate its robustness and reliability, the results were compared to those arising from the common liquid chromatographic method.

Development and Evaluation of Chemometric Models for the Estimation of Sumatriptan in the Presence of Naproxen and a Degradation Product Using UV Spectrophotometry.

Chemometrics is a discipline that allows the spectral resolution of drugs in a pharmaceutical formulation along with degradation product and it is as an alternative to chromatographic methods. Sumatriptan (SUM) is co-formulated with naproxen (NAP) and used in acute migraine attacks. SUM which has physiological importance has not been subjected to any stability-indicating chemometric approaches yet so there is a need for accurate and safe method for the assay of the cited drug in their preparation. SUM was determined in pharmaceutical formulation along with NAP and in presence of alkali-induced degradation product with simple and cost-effective multivariate approaches using spectrophotometric data. The greenness and blueness assessment was applied using different ecological metrics, including green analytical procedure index (GAPI), analytical greenness metric (AGREE), analytical eco-scale (AES) & new "blueness" evaluation using BAGI tool, respectively. Three chemometric approaches were applied for the stability-indicating determination of SUM in presence of NAP. Classical least squares (CLS), Partial least squares (PLS) and Principal components regression (PCR), three multivariate calibration numerical models that were performed on the UV- spectra of the mixtures, were used to achieve the best resolution. Sumatriptan was analyzed with mean accuracies for PLS (100.29 ± 1.318) and for PCR (100.60 ± 1.564). The presented methods were compared and validated for their quantitative analyses. Moreover, statistical comparison between the results obtained by the proposed models and the official methods showed no significant differences. The proposed multivariate calibrations were accurate and specific for quantitative analysis of the studied component. PLS is the best method that has the capacity for qualitative analysis of SUM and it is suitable for routine analysis and stability studies of it in quality control laboratories. Various ecological assessment metrics confirmed the long-standing eco-friendliness of the suggested models.

Quantitative determination of lobeglitazone sulfate and glimepiride in combined tablet by robust high‐performance thin layer chromatographic method

AbstractA combination of fixed dose tablet containing 0.5 mg lobeglitazone sulfate (LBZ) and 1 mg glimepiride (GLM) has demonstrated efficacy in enhancing glycemic control in diabetes. The projected work aimed to develop and validate a high‐performance thin‐layer chromatographic (HPTLC) methodology for the precise quantification of both the drugs in tablet formulations. The HPTLC analysis utilized aluminium plates layered with silica gel 60F254, and the solvent system consisted of ethyl acetate, benzene, and hexane (4:3:1 v/v/v) followed by densitometric scanning at 238 nm. The Rf value was found to be 0.68 ± 0.001 for LBZ and 0.48 ± 0.002 for GLM. The methodology exhibited linearity in the range of 100–2000 ng/band for LBZ and 200–4000 ng/band for GLM, with correlation coefficients of 0.9988 and 0.9981, respectively. Exceptional sensitivity was observed, with detection limits of 23.86 ng/band for LBZ and 58.26 ng/band for GLM, along with quantification limits of 72.32 ng/band for LBZ and 176.55 ng/band for GLM. The method demonstrated precision (% relative standard deviation of peak area < 2) and accuracy (recovery between 97% and 102%). The suggested method is suitable for quantifying both the drugs in tablets, making it useful for routine quality control in laboratories.

Electrochemical strategies for determination of tert-butyl hydroquinone (TBHQ) in food samples

AbstractTert-butyl hydroquinone (TBHQ) is a member of the synthetic phenolic antioxidant family that prevents the formation of free radicals and prevents radicals from damaging cells by trapping them. In addition, TBHQ is widely preferred as an additive in foods and vegetable oils because of its low cost and high chemical stability. TBHQ is not only a food preservative but is also frequently used as a stabilizer to prevent auto-polymerization in cosmetics, biodiesel, pharmaceuticals, coating products, and different application areas. TBHQ has been shown to cause diseases, such as DNA damage, carcinogenesis, and cell apoptosis, when administered at high doses. Excessive consumption of TBHQ causes adverse effects, such as stomach tumors, liver damage, and underdevelopment of the reproductive system. Different analytical methods have been used to detect TBHQ in food samples. The most important of these methods are traditional analytical methods such as chromatographic and spectrophotometric methods. However, these methods have basic shortcomings such as high analysis costs, long pre-processing, expensive equipment, need for many organic solvents, requiring expertise, and long detection times. In recent years, electrochemical sensors have attracted attention in the scientific world owing to their high sensitivity, fast analysis time, portability, low cost, and convenience of miniaturization. This review discusses electrochemical studies performed to date for the determination of TBHQ in food samples. The methods used in these studies have been evaluated in a wide range of aspects, such as the electrode, working range, detection limits, and analytical applications.

Antibacterial and Antioxidant Compounds from the Root Extract of Aloe debrana.

This study was conducted to isolate and identify the chemical compounds from the roots of Aloe debrana (L.) and evaluate their antioxidant and antibacterial activities. From the acetone (99.5%) extract of the roots of this plant, four anthraquinones, such as chrysophanol (1), asphodeline (2), aloesaponarin I (5), and laccaic acid D-methyl ester (6), and a new catechol derivative, 5-allyl-3-methoxybenzene-1,2-diol (3), were isolated and elucidated by different chromatographic and spectroscopic methods together with linoleic acid (4), respectively. Compounds 2, 3, and 4 were reported here for the first time from this plant and compound 3 from the genus Aloe. The compounds were evaluated for their antioxidant activity using H2O2 and DPPH assays and bactericidal activity against S. aureus and E. coli. Compounds 3 and 6 showed highest antioxidant activities with IC50 values of 19.38 ± 0.64 and 32.81 ± 0.78 μg/mL in DPPH, and 28.52 ± 1.08 and 27.31 ± 1.46 μg/mL in H2O2, respectively. The isolated compounds also demonstrated considerable activity towards S. aureus. Among these compounds, compound 3 exhibited the highest activity (91.20 ± 0.12% and 9.14 ± 0.93 mm at 1.0 mg/mL) against this bacterium. The overall results suggest that the isolated compounds may be considered as potential sources of the bioactive agents to be used in the pharmacological, food, and other industries. Moreover, their high sensitivity against S. aureus may also support the use of A. debrana plant in the traditional medicine to treat wounds. Therefore, the isolated compounds are responsible for medicinal properties of this plant.

Exploring advanced strategies in SPME-HPLC-DAD: Enhancing analytical precision and diverse applications in modern era

In analytical chemistry, the synergy between innovative sample preparation techniques and advanced chromatographic methods has paved the way for unprecedented advancements in the analysis of complex samples. Solid Phase Microextraction (SPME) stands out as a powerful tool for extraction, and preconcentration. When coupled with High-Performance Liquid Chromatography (HPLC) equipped with a Diode Array Detector (DAD), the integrated SPME-HPLC-DAD system emerges as a sophisticated analytical platform, offering enhanced sensitivity, selectivity, and versatility for various applications. Desorption is accomplished by either depositing organic solvent in the desorption chamber or else by flowing the mobile phase through the desorption chamber specificity. An ordinary description, along with a visual illustration, has been thoroughly provided for concepts of developed well-known enhanced thin film SPME cartridges (Figure 2). The tabular representation is also available with proper description like technique name, targeted analyte, column used, mobile phase used, %RSD, extraction recovery, LOD, and data acquired R2 also considered Based on the information available in the present study. Discussed SPME with HPLC-DAD brings a great turning point by successfully utilization in biomedical sciences, environmental monitors, food safety, and clinical analysis This cost-effective, readily available technique is both environmentally friendly and stable, allowing for rapid, reliable, and accurate measurements across a wide range of analyte concentrations, thanks to the utilization of hyphenated techniques. The different strategies of SPME with HPLC -DAD and possible future apllications have been incorporated in the review. The understanding of these techniques is still limited and challenging.

Comparative Study of Gas and Liquid Chromatography Methods for the Determination of Underivatised Neutral and Acidic Cannabinoids and Cholesterol.

The aim of our study was to develop a gas chromatographic method coupled with mass spectrometry (GC-MS) for the determination of underivatised neutral (CBDs-N) and acidic (CBDs-A) cannabinoids (CBDs) and cholesterol (Chol). Emphasis was also placed on comparing our original GC-MS method with the currently developed C18-high-performance liquid chromatography with photodiode detection (C18-HPLC-DAD). A combination of a long GC column, shallow temperature column programme, and mass-spectrometry was employed to avoid issues arising from the overlap between CBDs and Chol and background fluctuations. The pre-column procedure for CBDs and Chol in egg yolks consisted of hexane extractions, whereas the pre-column procedure for CBDs in non-animal samples involved methanol and hexane extractions. CBDs-A underwent decarboxylation to CBDs during GC-MS analyses, and pre-column extraction of the processed sample with NaOH solution allowed for CBD-A removal. No losses of CBDs-N were observed in the samples extracted with NaOH solution. GC-MS analyses of the samples before and after extraction with NaOH solution enabled the quantification of CBDs-A and CBDs-N. CBDs-A did not undergo decarboxylation to CBDs-N during C18-HPLC-DAD runs. The use of the C18-HPLC-DAD method allowed simultaneous determination of CBDs-N and CBDs-A. In comparison to the C18-HPLC-DAD method, our GC-MS technique offered improved sensitivity, precision, specificity, and satisfactory separation of underivatised CBDs and Chol from biological materials of endogenous species, especially in hemp and hen egg yolk. The scientific novelty of the present study is the application of the GC-MS method for quantifying underivatised CBDs-A, CBDs-N, and Chol in the samples of interest.