Reversed-phase High-performance Liquid Chromatographic Method Research Articles

Validated Rp-Hplc Method For The Sensitive Determination Of Potent Hormonal Drug Residues In Support Of Cleaning Validation In Pharmaceutical Manufacturing Equipment Surfaces

The detection and quantification of potent hormonal drug residues on pharmaceutical manufacturing equipment surfaces are paramount for ensuring product safety and efficacy, particularly during cleaning validation. This paper presents the development and validation of a reversed-phase high-performance liquid chromatography (RP-HPLC) method for the sensitive determination of hormonal drug residues in pharmaceutical manufacturing environments. The validated method demonstrates high specificity, accuracy, and sensitivity for detecting residues even at trace levels, which is essential for maintaining cleaning standards and preventing cross-contamination between drug products. The study explores the challenges of residual analysis, method optimization, and regulatory requirements in the pharmaceutical industry, underscoring the importance of robust analytical tools in maintaining pharmaceutical production quality.

A Cost-Effective Nonaqueous Reversed-Phase High-Performance Liquid Chromatography Method to Measure Vitamin D3 in Hen's Egg Yolk.

The objective of this study is to develop an HPLC-UV method for the cost-effective and quantitative determination of vitamin D3 in food, even in the presence of vitamin D2, with a specific focus on egg yolk. During method development, the performance of three stationary phases in resolving the peak of vitamin D2 from that of vitamin D3 was investigated. The physicochemical properties of these phases differed particularly in the extent of hydrophobicity and silanophilic activity, including a GraceSmart RP C18 column without silanol endcapping, a Robusta RP C18 column with silanol endcapping, and a Waters Xbridge RP C18 column with ethylene-bridged hybrid (BEH) particle technology. The Xbridge C18 stationary phase exhibited the most favorable performance, leading to an RS of 1.6 under the following nonaqueous reversed-phase (NARP) experimental conditions: mobile phase, acetonitrile, methanol, and trifluoroacetic acid in a (99/1/0.1, v/v/v) ratio; column temperature, 15°C. The developed chromatographic method does not require preanalytical purification steps and is also compatible with mass spectrometry. The identity of the vitamin D3 peak observed in the HPLC analysis was verified via GC-MS. The NARP-HPLC-UV method was partially validated, demonstrating satisfactory linearity, precision, accuracy, limit of quantification, and robustness. The HPLC method was then successfully applied to the analysis of real egg yolk samples, revealing average concentrations of vitamin D3 of 4-5µg/g of wet weight sample.

Development and validation of a RP-HPLC method for simultaneous determination of cimetidine, metoprolol tartrate and phenol red for intestinal perfusion studies.

A new reversed phase high-performance liquid chromatography (RP-HPLC) method, with a short analysis time and easy to apply, was developed for the simultaneous detection of cimetidine (CIM), metoprolol tartrate (MT) and phenol red (PR) for use in intestinal perfusion studies. The analysis was performed with phosphate buffer (pH 5.0, 12.5mM)-acetonitrile mixture as mobile phase and C18 column (Inertsil ODS-3; 5µm, 4.6×250 mm) as stationary phase. Gradient analysis conditions were used and the acetonitrile ratio in the mobile phase varied from 10 to 50% in 10min. Total run time for analysis was 10min and the injection volume was 20µL. Detection of compounds was performed at 207nm. Under optimum HPLC conditions, retention times were 4.03min for CIM, 6.99min for MT and 8.49min for PR. The method was validated according to ICH Q2 (R1) guideline for specificity, linearity, sensitivity, precision, accuracy, stability and robustness. Developed method was linear and determination coefficients of the calibration curves were 0.9993, 0.9991 and 1.0 for CIM, MT and PR, respectively. The limits of quantification were 6.20, 2.78 and 0.45μg/mL for CIM, MT and PR, respectively. The precision and accuracy values of the developed analytical method met the ICH Q2 (R1) limits. The applicability of the method was demonstrated by preliminary in-situ intestinal perfusion studies. In conclusion, samples obtained from in-situ intestinal perfusion studies performed to examine the absorption/permeability of CIM, MT, and PR can be analyzed with the developed HPLC method.

Development and validation of RP-HPLC method for simultaneous estimation of lidocaine and nifedipine in pure and combined dosage form

The simultaneous estimation of Lidocaine and Nifedipine using reversed-phase high-performance liquid chromatography (RP-HPLC) is essential for analysing both the bulk drug and its topical dosage form. The objective of this study was to develop a novel HPLC method for the simultaneous estimation of Lidocaine and Nifedipine. The method aimed to provide accurate and precise results for both the bulk drug and topical dosage form. The HPLC method employed a C18 column measuring (150 mm × 4.6 mm × 5 µm). A mobile phase consisting of a mixture of methanol and water in a ratio of 80:20 v/v was used. The flow rate was set at 1.0 ml/min, and the detection wavelength was set at λ-max 236 nm. The retention time for Lidocaine was determined to be 2.560 min, while for Nifedipine it was found to be 5.470 min. The developed HPLC method demonstrated good linearity for both Lidocaine and Nifedipine, as evidenced by the obtained correlation coefficients (R2) of 0.9890 and 0.9986, respectively. The accuracy studies yielded results within the acceptable range of 98.11% - 105%. Additionally, the precision of the method was established with % RSD values of less than 2% for routine analysis of lidocaine and nifedipine. This method provides a reliable and effective approach for the simultaneous estimation of lidocaine and nifedipine, contributing to the quality control and safety assessment of pharmaceutical formulations containing these compounds.

Development and Validation of RP-HPLC Method for Roflumilast Nano Particles in Rat Plasma for Pharmacokinetic Study Analysis

Aim: The aim of this study is to develop a sensitive, specific, rapid, and precise reverse- phase high-performance liquid chromatography (RP-HPLC) method and validate it to determine the Roflumilast in rat plasma. Background: This study was aimed at developing a simple HPLC method for the detection of Roflumilast in rat plasma after ingestion of nanoparticles into the rat. A bioanalytical method was developed and validated. Methodology: The drug sample (Roflumilast) was eluted isocratically using a mobile phase of Ammonium acetate buffer (pH = 7.0), acetonitrile, and methanol (20:40:40, v/v/v) made up the mobile phase on a Phenomenex C-18 (150mm x 4.68mm pore size 5-micron analytical column. The drug was quantitatively determined at a UV wavelength of 254 nm using a standard calibration curve spanning the range of 1.5, 3.0, 4.5, 6.0, 7.5μg/mL-1 Results: The results showed that the limits of quantitation (LOQ) and detection (LOD) were 0.18 μg/ml and 0.54μg/ml, respectively. For both the intra-day and inter-day analysis, relative standard deviation (% RSD) was less than 2%, and the drug’s percentage accuracy was between 96% and 98%. Conclusion: As per the established protocols, the developed method was quantitatively assessed for its intended use in terms of specificity, linearity, accuracy, precision, robustness, and sensitivity analysis. Roflumilast-loaded nanoparticles were effectively used to determine the drug entrapment efficiency using the currently validated RP-HPLC method. Besides, highly efficient drug extraction from plasma was attained, and mobile phase composition was suitable to the pharmacokinetic study of Roflumilast-loaded nanoparticles in rats. other: NA

Development And Validation of a RP-HPLC Method For Simultaneous Estimation of Risperidone and Trihexyphenidyl Hydrochloride in Pharmaceutical Formulations

A rapid and sensitive reversed-phase high-performance liquid chromatography (RP-HPLC) method was developed and validated for the simultaneous determination of Risperidone and Trihexyphenidyl hydrochloride in pharmaceutical formulations. The chromatographic separation was achieved using a Thermosil C18 column (4.0×125mm, 5μm) with a mobile phase consisting of methanol and sodium acetate buffer (pH 3.0) in the ratio of 70:30 v/v. The flow rate was maintained at 1.0 mL/min with UV detection at 252 nm. The retention times for Risperidone and Trihexyphenidyl hydrochloride were 2.566 and 3.417 minutes, respectively. The method demonstrated excellent linearity in the concentration ranges of 5-25 μg/mL for Risperidone and 50-250 μg/mL for Trihexyphenidyl hydrochloride, with correlation coefficients of 0.999 for both compounds. The method validation parameters including accuracy, precision, specificity, and robustness met ICH guidelines. The mean recoveries were 99.56% and 99.48% for Risperidone and Trihexyphenidyl hydrochloride, respectively. The limits of detection were 3.17 μg/mL and 0.0172 μg/mL, while the limits of quantification were 5.80 μg/mL and 0.212 μg/mL for Risperidone and Trihexyphenidyl hydrochloride, respectively. The validated method proved suitable for routine quality control analysis of both drugs in pharmaceutical formulations.

Preparation and in-vitro characterization of triamcinolone acetonide-loaded lipid liquid crystal nanocarriers for ocular delivery

Purpose: This study aimed to develop sustained-release Triamcinolone acetonide (TA) formulations using lipid liquid crystals (LLC) for ocular drug delivery and to characterize the designed formulations. Method: Eighteen dispersed LLC formulations were prepared through a top-down approach, incorporating varying concentrations of TA and different proportions of glyceryl monooleate, deionized water, and Pluronic F127. An additional formulation comprising TA: HPβCD complex was also developed to investigate the influence of hydroxypropyl beta-cyclodextrin (HPβCD) on the properties of the formulations. The formulations were evaluated for their rheological properties in room temperature using a rheometer, syringeability by passing them through a 27G needle, size measurements via dynamic light scattering, and morphology through polarized light microscopy (PLM). Furthermore, the prepared formulations were injected into a dialysis tube and placed in a phosphate buffer at pH 7.4 and 37°C for in vitro release evaluation. Samples were taken at predetermined intervals and stored in a refrigerator until HPLC analysis. The percentage of Encapsulation efficacy and drug loading were evaluated using an indirect method. A reversed-phase HPLC method was employed to quantify the drug concentrations in the samples. Results: All selected formulations demonstrated acceptable parameters, including particle size (less than 200 nm), polydispersity index ranging from 0.202 to 0.355, and zeta potential values between -14.3 and -32.8 mV. Additionally, the formulations showed good syringeability and achieved 100% drug release within 48 hours (except for the formulation containing HPβCD). PLM analysis revealed the presence of hexosomes and cubosomes, indicating that an increase in hexosomes contributed to a more uniform drug release from the formulations. Conclusion: Overall, the study findings suggest that liquid crystalline carriers can be a promising formulation for sustained ocular drug delivery of TA.

Impact of fresh grape juice on the pharmacokinetics of omeprazole: results of a food-drug interaction study.

Grapes have been widely used for dietary ailments due to their attributed pharmacological activities. Resveratrol, the chief constituent of grapes, is responsible for their pharmacological benefits. However, apart from their beneficial effects, grapes have also recently been considered in drug interaction studies. This study investigated the pharmacokinetic profile of omeprazole administered alone compared to omeprazole administered with grape juice, with a prior intake of grape juice, for 1 continuous week. The study was conducted on two groups of healthy male volunteers [n = 12]. One group was orally administered 40mg of omeprazole alone, while the other group was administered omeprazole with grape juice. Blood samples were analyzed for omeprazole concentration by a reverse-phase HPLC method. Co-administration of 40mg omeprazole with grape juice significantly decreased the AUC0-t and Cmax by 32% and 34%, respectively, suggesting a role being played by grapes in the activation of P-glycoprotein and omeprazole metabolizing enzymes, including CYP3A4 and CYP2C19. In conclusion, the addition of grapes as a dietary supplement in patients taking omeprazole for the management of peptic ulcer symptoms may lead to a higher required dose of omeprazole.

Stability-Indicating RP-HPLC Method Development for the Determination of Empagliflozin

Aim: This study aimed to develop and validate a stability-indicating reverse-phase high-performance liquid chromatography (RP-HPLC) method for the quantitative analysis of empagliflozin in pharmaceutical formulations. Materials and Methods: The method was developed using an Agilent C18 column (5μm; 4.6 x 250 mm) and a mobile phase consisting of a mixture of methanol/ 0.05% pH 3.3 acetic acid (75:25) at a flow rate of 1 ml/min with UV detection at 224 nm. The developed RP-HPLC method demonstrated linearity with a correlation coefficient (r) of >0.999. Forced degradation studies revealed the method’s ability to separate and quantify empagliflozin from its degradation products. The actual percentage degradation ranged from 2.85% to 7.43%. Precision was established where the mean interday and intraday RSD were 0.36% and 0.17%, respectively. Result and Discussion: The method’s robustness was confirmed, which had negligible effects on the assay results (<0.2% RSD). The method was applied to commercially available tablets, yielding an average (SD) empagliflozin recovery of 100.44% (0.18). Conclusion: This RP-HPLC method is suitable for routine analysis of empagliflozin in pharmaceutical formulations and can be employed for stability studies and quality control purposes, ensuring the drug’s quality and efficacy throughout its shelf life.

Stability indicating reverse-phase high-performance liquid chromatographic method development for simultaneous estimation of benidipine HCl and nebivolol HCl in bulk and dosage form, and assessment of its green chemistry....

The present study aimed toward the evaluation of the fixed-dose combination of two antihypertensive drugs in combination in the formulation and bulk by a reverse-phase high-performance liquid chromatographic (RP-HPLC) method and the stability evaluation is done according to the International Council for Harmonisation (ICH) guidelines. Benidipine HCl and nebivol HCl were simultaneously estimated in bulk and pharmaceutical dosage form using the RP-HPLC method. The developed method was validated as per ICH guidelines. The drugs were separated using Hypersil™ octadecylsilane C19 HPLC Column (250 x 4.6 mm ID, 5 μm). 70:30 v/v of methanol and 0.1% orthophosphoric acid (OPA) were selected as the mobile phase. A fixed wavelength of 228 nm and 1 mL/min flow rate were selected. The retention time for benidipine HCl and nebivolol HCl were 2.078 and 3.625 min with 10.4 resolution. A linear relationship with a correlation coefficient of 0.999 was found in the concentration range of 4-12 μg/mL for benidipine HCl and 5-15 μg/mL for nebivolol HCl. The percentage recoveries were 99.36% for benidipine and 99.32 for nebivolol, respectively. The precision values for benidipine HCl and nebivolol HCl were found to be 1.3% and 0.27%, respectively. The limit of detection (LOD) and limit of quantification (LOQ) values for benidipine HCl have been estimated to be 0.068 μg/mL and 0.227 μg/mL, respectively. Similarly, for nebivolol HCl, the LOD and LOQ values were found to be 0.0862 μg/mL and 0.287 μg/mL. Furthermore, degradation studies and green assessments were carried out. The green assessment was carried out using AGREE and the green analytical procedure index, and the method was found to be green. The optimized approach is safe, economical, with shorter retention periods, and stability, and also adheres to the green analytical chemistry profile, making it appropriate for regular quality control testing in the pharmaceutical sector.. KEYWORDS :AGREE, Benidipine HCl, Nebivolol HCl, RP-HPLC.

Green RP-HPLC method for simultaneous quantification of epigallocatechin-3-gallate and rosmarinic acid in lipid-based nanocarriers and biological fluids: Quality by Design-driven optimization and lean six sigma approach

This study presents the development and validation of a reverse-phase high-performance liquid chromatography (RP-HPLC) method for concurrent quantification of EGCG and RA in prepared lipid-based nanocarriers and biological fluids using a QbD approach, greenness assessment, and Six-Sigma methodology. Initially, variations in critical analytical attributes were identified using the Ishikawa fishbone diagram and Risk Priority Number scores. A Taguchi Orthogonal Array design was employed to screen the critical method parameters influencing method development. Systematic optimization of the RP-HPLC method was subsequently achieved using a Box-Behnken design, with the % organic phase, flow rate, and column temperature as the variables. The responses were retention time, tailing factor, and theoretical plates for both EGCG and RA. Chromatographic separation was accomplished with a methanol and 0.1% formic acid (60:40) isocratic flow system on a Phenomenex Luna C18 column (4.6 × 250 mm, 5 μm) at a 1 mL/min flow rate. The method was rigorously validated according to ICH guidelines. Linearity was observed over a concentration range of 2 to 10 µg/mL for both EGCG and RA, yielding correlation coefficients of 0.998 and 0.999, respectively. The LOD and LOQ were determined to be 0.51 µg/mL and 1.54 µg/mL for EGCG, and 0.35 µg/mL and 1.07 µg/mL for RA. Moreover, the %RSD for all validation parameters were consistently below 2%. Forced degradation studies were conducted under acidic, basic, oxidative, and photolytic conditions to elucidate potential degradation pathways and identify degradation products. The developed method was applied to estimate EGCG and RA in prepared lipid-based nanocarriers and biological fluids like blood plasma and urine. Recovery assays in lipid-based nanocarriers, plasma, and urine samples demonstrated excellent recoveries (96.2–102.1%). The method's greenness was assessed using various tools, and its accuracy was evaluated using Six Sigma methodology. Overall, the developed HPLC method offers a rapid, sensitive, and reliable approach for quantifying EGCG and RA, laying the groundwork for their further investigation as anticancer agents, alone and in combination therapies.

Development of a reverse-phase high-performance liquid chromatography method for highly sensitive determination of etravirine (4-[[6-amino-5-bromo-2-[(4-cyanophenyl)amino]-4- pyrimidinyl]oxy]-3,5-dimethyl benzonitrile) in pure drug and formulations

Etravirine (ETR) is a heterocyclic diarylpyrimidine derivative with the following chemical name 4-([6-amino-5- bromo-2-[(4-cyanophenyl)amino]-4-pyrimidinyl]oxy)-3,5-dimethylbenzonitrile. Complex chemical structures with nitrogen and oxygen atoms create chemical reactivity as well as specificity in the binding. Advanced chromatographic techniques must be used for correct quantification and stability analysis during pharmaceutical applications. By lowering the use of organic solvents and following strict validation guidelines, a novel reverse-phase high-performance liquid chromatography method for ETR was developed and validated as effective, dependable, and environmentally friendly. An isocratic eluting method was developed using acetonitrile and buffer (25 mM potassium dihydrogen phosphate in water) at a ratio of 30:70 (%v/v) with a flow rate of 1.0 mL/min in a Kromasil C18 column at 310 nm. It was found to be linear around 1.50-10.50 μg/mL, with a r2 value of 0.9994. The AGREE tool for evaluating greenness resulted in a score of 0.57, and another tool called the analytical method greenness scored 839.17 and ensured the greenness of the method. The developed method is simple, sensitive, precise, accurate, robust, and reproducible for the analysis of ETR in bulk and tablet formulations for routine analysis.. KEYWORDS :Antiviral, Etravirine, Ultraviolet-visible, High-performance liquid chromatography, Method development and validation, Green method.

A generalizable methodology for predicting retention time of small molecule pharmaceutical compounds across reversed-phase HPLC columns.

Quantitative structure retention relation (QSRR) is an active field of research, primarily focused on predicting chromatography retention time (Rt) based on molecular structures of an input analyte on a single or limited number of reversed-phase HPLC (RP-HPLC) columns. However, in the pharmaceutical chemistry manufacturing and controls (CMC) settings, single-column QSRR models are often insufficient. It is important to translate retention time across different HPLC methods, specifically different stationary phases (SP) and mobile phases (MP), to guide the HPLC method development, and to bridge organic impurity profiles across different development phases and laboratories. In response to this need, we present a novel approach for retention time transfer across SPs and MPs, without requiring pre-existing Rt data on the target column. To achieve this, we developed an RP-HPLC based Genentech Multi-column Retention Time (GMCRT) database containing 51 small molecule pharmaceutical compounds analyzed on twenty SPs and multiple pH levels. The database incorporated the SP selectivity parameters from Hydrophobic Subtraction Model (HSM) - hydrophobicity (H), steric hindrance (S), hydrogen-bond acidity (A), hydrogen-bond basicity (B), ionic interaction (C) under two different pHs (2.8 and 7) and ethylbenzene (EB) retention factor. Two machine learning approaches, partial least squares (PLS) and artificial neural networks (ANN) were found to improve accuracy of Rt prediction on new SPs compared to the direct mapping approach that have been previously published, especially when the RP-HPLC columns have significant selectivity difference. As a comparison, our approach does not require pre-existing retention data on the target SPs and it is generalizable to any RP-HPLC columns with a set of known column selectivity parameters (https://www.hplccolumns.org/). The generalizability is achievable not only via the available retention data correlation among the twenty commonly-used RP-HPLC columns in GMCRT, but also via the retrainable mechanism of our ML models by adding Rt of the compounds of interest on the source columns into GMCRT, followed by predicting Rt on the target column. Thus, we propose a new QSRR framework that incorporates the physiochemical properties of SPs and MPs and makes the retention time prediction transferable across SPs and MPs. Such a framework is expected to open up possibilities for developing more comprehensive and generalizable models, and streamline RP-HPLC method development and lifecycle management across various pharmaceutical CMC development phases.

Development of HPLC-UV method for determination of Nilotinib in spiked human plasma with greenness assessment

One of the approved second-generation tyrosine kinase inhibitors (Nilotinib) shows great efficacy and selectivity in the treatment of patients with chronic or accelerated phase chronic myelogenous leukemia, and in resistant/ intolerant to prior therapy cases. For the analysis of Nilotinib in synthetic mixture and human plasma samples, a new reversed-phase high-performance liquid chromatographic method was developed. Determination was performed successfully using RP–18 column and a mobile phase consisting of 10 mM potassium dihydrogen phosphate buffer (pH = 5.5), methanol, and acetonitrile in the ratio 37:37:26 (v/v/v). Isocratic mode of elution with flow rate 1.2 ml/min and UV detection at 265 nm were applied. The method was validated for linearity in the range 0.5–24.0 µg/ml and best accuracy and precision results were obtained at temperature 40 °C. The percentage recovery of the analyzed drug was in the range 88.0–106.0 %. Moreover, the proposed RP-HPLC method was evaluated in terms of greenness, whiteness and blueness using three newly developed ecological metrics – The Analytical Greenness software, White Analytical Chemistry and Blue Applicability Grade Index. Good results were obtained and the technique was proved effective, specific and suitable for implementation in routine quality control and clinical laboratory practice for therapeutic drug monitoring.

Development and validation of a robust RP-HPLC method to quantitate residual 2–mercaptoethylamine in drug product formulations containing amino acid additives

Bispecific antibodies have a wide range of applications in cancer immunotherapy, some of which are manufactured by controlled Fab-arm exchange requiring the reductant 2-mercaptoethylamine (2-MEA). As a process impurity, monitoring the residual 2-MEA in bispecific antibody drug product process development is needed. A novel reversed phase-high performance liquid chromatography (RP-HPLC) method for measurement of residual 2-MEA that uses 7–fluorobenzofurazan-4-sulfonic acid ammonium salt (SBD-F) as a fluorescent-detection tag in drug product formulations containing high concentrations of arginine has been developed. Using a thiol tag for residual 2–MEA eliminates any potential interference from conventional tag binding to amine groups of the formulation arginine, and potentially resulting in overestimation of the amount of impurity in a given sample. The new method has been fully validated for specificity, linearity, accuracy, range, limit of quantitation, limit of detection, and robustness. This method therefore has potential to aid in detecting residual 2-MEA content for any process that utilizes 2-MEA for bispecific antibody manufacturing.

Novel analytical approach for baclofen quantification in rodent plasma.

A simple, accurate, and robust reverse-phase high-performance liquid chromatography (RP-HPLC) method was developed and validated for the quantification of Baclofen in rat plasma. The method demonstrated high degree of linearity (r2 = 0.9936) across a concentration range of 10-50 μg/mL. Precision, accuracy, limit of detection (LOD), limit of quantification (LOQ), and robustness were evaluated according to ICH guidelines. The LOD and LOQ were found to be 0.076197 and 0.23090 μg/mL, respectively. This method provides an efficient approach for Baclofen quantification in plasma, making it suitable for pharmacokinetic and bioavailability studies. The novelty of this study lies in its optimization for routine use in laboratories, ensuring reproducibility with minimal variations across different conditions and analysts.

Eco-friendly RP-HPLC approach for simultaneously estimating the promising combination of pentoxifylline and simvastatin in therapeutic potential for breast cancer: Appraisal of greenness, whiteness, and Box–Behnken design

Abstract Breast cancer affects millions of women worldwide. This study explores the potential of combining pentoxifylline (PTX) and simvastatin (SIM) as a treatment for breast cancer. We aimed to develop six sustainability tools using green and white metrics to evaluate the environmental impact of reversed-phase high-performance liquid chromatography (RP-HPLC) methods for analyzing and separating PTX and SIM in their pure forms. The tools include analytical GREEnness, green analytical procedure index, Complexgreen analytical procedure index, analytical greenness metric for sample preparation, blue applicability grade index, and the RGB 12 algorithm. For the separation, we used a Novapack C8 column (15 × 0.46 cm, 5 µm) at 25°C. The injection volume was 5.0 µL, the wavelength was set to 210 nm, and the total runtime was 5 min. We identified optimal chromatographic conditions efficiently using the Box–Behnken design with minimal trials. We investigated the effects of three factors on retention time and resolution: acetonitrile ratio, pH, and flow rate. We used overlay plots with a 60:40 ratio (v/v) of acetonitrile and bi-distilled water to forecast the most effective mobile phase. The calibration curves for PTX and SIM showed a correlation value of over 0.999 within the range of 5–60 µg·mL−1. The recovery rates ranged from 99.9% to 100.2%, indicating high accuracy. Our RP-HPLC technique proves to be reliable and efficient for the simultaneous estimation of multiple anticancer drugs. We evaluated the environmental sustainability of this approach using green and white metrics, and the recommended method has been thoroughly validated according to International Council for Harmonisation guidelines, making it highly reliable for analyzing new formulations.

TLC vs. HPLC: A green comparison for veterinary drug analysis

This work describes two analytical methods for determining lidocaine (LD) and oxytetracycline (OTC) in veterinary dosage form: a traditional Thin-Layer Chromatography (TLC) method and a more environmentally friendly Reversed-Phase High-Performance Liquid Chromatography (RP-HPLC) method.Initially, the TLC method was used due to its speed, simplicity, and accuracy. It successfully separated LD and OTC in veterinary dosage forms with a linearity range of 0.5–11.0 µg/band for LD and 4.0–34.0 µg/band for OTC. However, TLC proved to be inadequate for resolving the binary mixture in the presence of toxic lidocaine impurity (2,6-dimethylaniline) (DMA), and was less environmentally friendly.Consequently, an RP-HPLC method was developed using a C18 column and a mobile phase consisting of ethanol and phosphate buffer (pH 7) in a 70:30 ratio, with a flow rate of 1.0 mL/min. This method effectively separated OTC, LD and DMA, using a PDA detector at wavelengths of 272, 232, and 210 nm and with retention times of 1.529, 2.77, and 3.581 min for OTC, DMA, and LD respectively. The RP-HPLC method showed linearity ranges of 270.0–972.0 µg/mL for OTC, 0.5–25.0 µg/mL for DMA, and 5.0–18.0 µg/mL for LD.Both methods were validated for linearity, precision, accuracy, robustness, detection limit, and quantitation limit. The greenness of each method was evaluated using NEMI, Eco-scale, and Agree tools, with results demonstrating the RP-HPLC method as the more environmentally sustainable method.

A sustainable RP-HPLC method for simultaneously estimating aceclofenac, paracetamol, and serratiopeptidase with AQbD optimization

This study focused on developing and validating a novel method for the simultaneous estimation of aceclofenac (AFC), paracetamol (PCM), and serratiopeptidase (SPD) using reverse phase high-performance liquid chromatography (RP-HPLC). The method was designed based on Analytical Quality by Design principles, incorporating green and white analytical chemistry (WAC) to ensure environmental sustainability and analytical efficiency. The HPLC analysis was performed using an Agilent 1220 Infinity II system equipped with a PDA detector, binary solvent pump, and automatic injector. Separation was achieved on an Agilent Inertsil ODS 3 column (250 mm × 4.6 mm, 5 μm particle size) with a mobile phase of ethanol and a 10 mM phosphate buffer (pH 3), adjusted with 1 % orthophosphoric acid. A gradient elution method was employed with a flow rate of 0.8 mL/min and detection at 230 nm. The retention times for AFC, PCM, and SPD were found to be 3.5, 5.2, and 8.9 min, respectively. Method validation confirmed accuracy and precision, with relative standard deviation (RSD) values consistently below 2 %, and a linearity range that met acceptable analytical standards. The integration of green and white analytical chemistry principles enhanced the method's sustainability, reducing environmental impact while ensuring minimal revalidation requirements. By adopting WAC, the method demonstrated simplicity, stability, and a strong alignment with sustainable chemistry practices. This method serves as an innovative and environmentally friendly approach for the accurate analysis of pharmaceutical compounds.

Application of Reversed-Phase HPLC Method for the Simultaneous Determination of Lenacapavir and Bictegravir in Tablets Dosage Form

Application of Reversed-Phase HPLC Method for the Simultaneous Determination of Lenacapavir and Bictegravir in Tablets Dosage Form