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The current investigation was pointed at developing and progressively validating novel, simple, responsive and stable RP-UPLC method for the measurement of active pharmaceutical ingredient of viloxazine. Attention deficit hyperactivity disorder (ADHD) is children and adults are treated by viloxazine, a selective norepinephrine reuptake inhibitor and viloxazine, selective nor-epinephrine reuptake inhibitor is used for treatment of ADHD in children six years or above of age. An easy, sensitive, specific and precise method for the pharmaceutical dose estimation of viloxazine in tablet dosage form was developed using RP-UPLC method. Separation was achieved by using BEH C18 100 × 2.1 mm, 2m column. Mobile phase containing OPA: Acetonitrile taken in the ratio 60:40 was pumped through column at a flow rate of 0.3 ml/min, and temperature was maintained at 300C. Optimized wavelength selected was 218.0 nm, and retention time of viloxazine was found to be 1.678 min. % RSD was found to be 0.9, % recovery and % assay was obtained as 100.44% and 99.90%, respectively. LOD and LOQ values were obtained as 0.30 µg/ml, 0.90 µg/ml. Recovery, specificity, linearity, accuracy, robustness, ruggedness was determined as a part of method validation and the results were found to be within the acceptable range. The proposed method to be fast, simple, accurate, feasible and affordable in assay condition. [ABSTRACT FROM AUTHOR]

The objective of the present effort is developing a fully green-assessed stability-indicating reverse phase liquid chromatography for the assessable measurement regarding Remogliflozin etabonate (RGE) & Teneligliptin (TEN) in drug substance and tablets and fully validated as per ICH criteria. Waters Atlantis T3 (150mm x 4.6, 3.5µm) column, 30 volumes acetonitrile along with 70 volumes ammonium formate (pH-3.0) mobile phase pumped at a flow rate of 1.0ml/min were used for the chromatographic separation using PDA exposure at 236 nm wavelength. Remogliflozin etabonate, Teneligliptin were separated at 2.730, 4.468 minutes of retention times respectively. ICH guidelines Q2 R1 was employed to validate the current procedure. Accuracy measurements were acceptable to intra-day and inter-day measurements. For RGE & TGN, respectively, the recommended technique was linear in the concentration ranges of 25-150µg/ml and 2.5-15 µg/ml. y=29777x+67797 and y= 30689 x +22270 respectively were the observed regression equations for RGE and TEN. The limits of detection (LOD) and quantification (LOQ) for Remogliflozin etabonate & Teneligliptin were respectively 0.3 (µg/ml), 1 (µg/ml) and 0.03(µg/ml), 0.1(µg/ml). The recovery percentage of the method was found to remain in between 98% and 100%. Q1A R2 and Q1B guidelines were followed for conducting stability-indicating studies. The technique can also be utilized for quality control and repetitive laboratories evaluation aimed at the simultaneous assessment of RGE & TEN in the drug substance and pharmaceutical dosage form. [ABSTRACT FROM AUTHOR]

This work presents the development and validation of a solid Reverse Phase High-Performance Liquid Chromatography (RP-HPLC) method for concurrently quantifying Cinnarizine and Piracetam in pharmaceutical formulations. The technique used an Agilent 1200 series high-performance liquid chromatography (HPLC) machine equipped with a C18 column. The mobile phase composition consisted of Methanol and Orthophosphoric Acid. Correlation coefficients of 0.9992 for Cinnarizine and 0.9998 for Piracetam indicate the calibration curves exhibit a robust linear relationship. The present investigation determined the Limits of Detection (LOD) for Cinnarizine to be 0.1575 µg/ml, other than for Piracetam it was found to be 1.9926 µg/ml. The Limits of Quantification (LOQ) for both compounds were found to be 0.4774 µg/ml and 6.0384 µg/ml, respectively. In interday precision tests, the approach exhibited a high level of accuracy, as evidenced by % Relative Standard Deviation (RSD) values of 0.3601 for Cinnarizine and 0.7080 for Piracetam. Assay results for Phescetam capsules revealed 100.53% purity for Cinnarizine and 100.19% for Piracetam, with % RSD values within acceptable limits, indicating high accuracy and precision. The method proved robust and rugged, showing consistent results under varying analytical conditions and across different analysts. Stability studies confirmed the method's suitability for routine quality control, with both drugs demonstrating stability under acidic, basic, oxidative, and photolytic conditions. [ABSTRACT FROM AUTHOR]

Background: Hypertension is a prevalent health condition with severe implications for cardiovascular health. Combination therapy involving Candesartan and Nifedipine has emerged as a promising approach for managing hypertension due to the synergistic effects of these medications. Methods: This study aimed to develop a Design of Experiment (DoE) based Green High-Performance Liquid Chromatography (HPLC) method for the simultaneous estimation of Candesartan and Nifedipine in a combined dosage form. Reversed-phase HPLC was utilized with UV-Vis spectrophotometry for detection. DoE principles were applied to optimize chromatographic conditions, including pH, ethanol percentage in the mobile phase, and flow rate. Results: Optimal chromatographic separation was achieved using a composite mobile phase comprising ethanol and potassium dihydrogen phosphate buffer (45:55, v/v) at pH 3.7, with a flow rate of 1 mL/min. Statistical analysis confirmed the significance of these parameters in achieving efficient separation. The developed method exhibited high precision, accuracy, and reliability across various validation parameters, including specificity, linearity, repeatability, and robustness. Conclusion: The proposed DoE-based Green HPLC method offers a sustainable and efficient approach for the simultaneous estimation of Candesartan and Nifedipine in hypertension management. By integrating green chemistry principles with systematic method development, this method provides a reliable analytical tool for routine quality control purposes in pharmaceutical formulations containing these medications. [ABSTRACT FROM AUTHOR]

A reversed-phase high-performance liquid chromatography (RP-HPLC) method was developed and validated for simultaneous quantification of Azelnidipine (AZN) and Telmisartan (TMN) in combined tablet dosage forms. Chromatographic separation was achieved using a C18 column (100 × 4.6 mm, 2.5 µm particle size) with a mobile phase consisting of Acetonitrile: pH 3 phosphate buffer (75:25, v/v) at a flow rate of 0.9 mL/min, with detection occurring at 237 nm. The method was validated according to International Conference on Harmonisation (ICH) guidelines, demonstrating linearity over the concentration ranges of 6.4-32 µg/mL for AZN and 16-80 µg/mL for TMN. The limits of detection (LOD) and quantitation (LOQ) were determined to be 0.4399 and 1.3332 for AZN, and 0.882 and 2.6729 for TMN, respectively. The method also exhibited precision, repeatability, and accuracy, with relative standard deviations (RSD) = 2% and accuracy ranging from 99-101%. To assess the method's stability-indicating capability, forced degradation studies were conducted under four stress conditions: acidic hydrolysis, alkaline hydrolysis, oxidative degradation, and thermal degradation. The results confirmed the method's ability to accurately quantify AZN and TMN in the presence of degradation products. [ABSTRACT FROM AUTHOR]

This study presents the validation of a reverse phase high performance liquid chromatographic technique (RP-HPLC) for the simultaneous measurement of hydrochlorothiazide and telmisartan in tablet and bulk dose forms. An ODS Inertsil C18 (150 × 4.6 mm, 5μ particle size) column was used for chromatography in isocratic mode. The mobile phase included 0.1% trifluoroacetic acid: acetonitrile (70:30) ratio. The eluent was measured at 225 nm and the flow rate was 1.2 ml/min. It was discovered that the chosen chromatographic conditions successfully separated hydrochlorothiazide (RT-2.70) and telmisartan (RT-9.98 min). It was discovered that the suggested approach was reliable, accurate, economical and resilient. It can be applied to the simultaneous study of these medications in tablet form. [ABSTRACT FROM AUTHOR]

The objective of this study is to develop simple, rapid and sensitive reversed-phase high performance liquid chromatography method for bilastine in tablet dosage form by quality by design approach. In reversed-phase high performance liquid chromatography method, chromatographic conditions such as mobile phase composition and flow rate were optimized with the help of Design-Expert software using central composite design. In this method, bilastine was estimated using octadecylsilane column (250×4.6 mm, 5 µm) and methanol:acetonitrile (90:10 % v/v) as mobile phase and flow rate 1 ml/min which are optimized using Design-Expert software. Method was developed at 280 nm detection wavelength. The retention time was found to be 3.484 min. The proposed method was successfully applied to the determination of bilastine in tablet dosage form. High linearity of developed method was confirmed over concentration range of (20-120) µg/ml and correlation co-efficient is 0.9997. The percentage relative standard deviation for precision and accuracy of the method was found to be <2 %. The recovery was in the range of 98.8 %-99.7 %; limit of detection was found to be 0.1352 µg/ml and limit of quantification was found to be 0.4098 µg/ml. Bilastine was found to degrade under oxidation condition. There was no interference of excipient and degradation product in retention time, so the method was specific. Analytical parameters such as precision, accuracy, limit of detection, limit of quantification and robustness were determined according to International Conference on Harmonization guidelines. [ABSTRACT FROM AUTHOR]

The present work reports an ultra-performance liquid chromatography (RP-UPLC) method for the quantitative determination of pioglitazone HCl (PGZ) in pharmaceutical dosage form. The chromatographic separation was performed on C18, BEH (50 mm x 2.1 mm, 1.7 μm) column using isocratic elution. The optimized mobile phase consists of phosphate buffer (pH:6) as a solvent-A and 55:45 v/v mixture of acetonitrile as solvent-B. Flow rate was 0.4 ml/min with UV detection at (λmax) 225 nm and the injection volume was set at 2 μL with retention time 1 min. The developed RP-UPLC method was validated as per International Conference on Harmonization (ICH) guidelines with respect to system suitability, specificity, precision, accuracy, linearity. [ABSTRACT FROM AUTHOR]

This study aims to develop an electrochemical method for determining cefprozil (CFP) and a stability-indicating chromatographic analysis method for determining CFP's isomers. CFP was determined for the first time via voltammetric methods in this study. The electrochemical behavior of CFP was examined over a pH ranging between 0.3 and 10.0 using cyclic voltammetry and differential pulse voltammetry (DPV). CFP oxidized irreversibly and by diffusion-controlled at a glassy carbon electrode. Quantification studies with DPV were carried out. The repeatability, reproducibility, sensitivity, precision, and accuracy of the method were statistically evaluated. To determine CFP's diastereoisomers, a high-performance liquid chromatography (HPLC) method was devised and validated using paracetamol as the internal standard. The moving phase, buffer solutions at various concentrations, pH, temperature, and flow rate impacts were all tuned in the experiments. The optimum separation via chromatography was sustained through the ACE 5 C8 (150 × 4.6 mm × 5 µm) column and acetonitrile: buffer solution (5 mM, ammonium acetate), 90:10 (v/v) mobile phase composition. The CFP diastereomers were separated at a flow rate of 1 mL min−1, 45 °C, and a wavelength of detection at 280 nm. The proposed method was validated in line with the International Conference on Harmonization guidelines, and HPLC degradation studies (oxidation, UV light, acid, base and temperature) were also performed. The proposed voltammetric and stability-indicating chromatographic methods have been successfully applied in pharmaceutical dosage forms. Thus, it has been shown that the analysis results were not affected by the excipients and their applicability to drug samples. Both methods were validated, and their applicability for analysis from synthetic biological samples will be demonstrated. The developed methods were fast, selective, sensitive, reliable, and environmentally friendly. [ABSTRACT FROM AUTHOR]

Context: Warfarin is extensively used for venous thromboembolism and other coagulopathies. In clinicalsettings, warfarin is administered as a mixture of S‑warfarin and R‑warfarin, and both enantiomers are metabolized by multiple cytochrome P450 enzymes into many hydroxylation metabolites. Validation of analysis method and estimation of warfarin plasma levels are important, especially in narrow‑index drugs such as warfarin. Aims: This study aimed to obtain a validated method for analyzing warfarin in patient plasma according to the European Medicines Agency (EMA) guidelines. Materials and Methods: A total of 77 patients were enrolled in this study. Five millimeters of venous blood was collected using sodium ethylenediaminetetraacetic acid (EDTA) tubes for pharmacokinetic analysis. Samples were prepared by the protein precipitation technique using acetonitrile. The optimum conditions for the analysis of warfarin in human plasma were tested using fluorescence detector (FLD) high‑performance liquid chromatography (HPLC) with Chiralcel OD‑RH column (4.6 × 150 mm i.d., 5 μm), Chiralcel OD‑RH guard column (4.0 × 10 mm, 5 μm), and a column temperature of 45°C. The mobile phase used was acetonitrile: phosphate buffer pH 2 (40:60), with an isocratic flow rate of 1 ml/min and an injection volume of 20 μl. Excitation and emission wavelengths were 310 and 350 nm (warfarin) and 300 and 400 nm (griseofulvin). The retention time of griseofulvin was 6–7.5 minutes; R‑warfarin was 10–11.5 minutes; and S‑warfarin was 14–16 minutes. Results: The result of this validation obtained the optimum conditions. This method yielded the limit of detection (LOD) values of 0.0674 ppm (R‑warfarin) and 0.0897 ppm (S‑warfarin). The limit of quantification (LOQ) values were 0.225 ppm (R‑warfarin) and 0.298 ppm (S‑warfarin). Linearity existed at concentrations of 0.2–3 ppm with the line equation y = 0.0705x + 0.0704 with R² = 0.978 for R‑warfarin and y = 0.0513x + 0.0297 with R² = 0.9924 for S‑warfarin. At least 75% of the seven concentrations met the reverse concentration requirements, which were below ± 15%. This method met the requirements of accuracy and precision within and between runs, selectivity, and carryover where the %RSD and %diff values were below ± 15%. The mean plasma concentrations of R‑warfarin and S‑warfarin were found to be 0.76 ± 1.87 (SD) μg/ml and 0.59 ± 0.81 (SD) μg/ml, respectively. The mean standard dose group plasma concentration from the analysis of 77 samples was 0.68 ± 0.61 μg/mL for R‑warfarin and 0.52 ± 0.42 μg/mL for S‑warfarin. Conclusions: Based on these results, this analytical method can be declared valid and can be used for sample measurement in warfarin pharmacokinetic studies. [ABSTRACT FROM AUTHOR]

Objectives: A straightforward, accurate, and precise reverse-phase high-performance liquid chromatography method was developed to determine the quantity of Lobeglitazone in both bulk and pharmaceutical dosage forms. Materials and Methods: The chromatographic separation was achieved on a Phenomenex Luna column with dimensions of 250 cm×4.6 mm×5 µm, and the mobile phase was a combination of potassium dihydrogen orthophosphate and acetonitrile in a 70:30 V/V ratio with a pH of 4.0, adjusted using orthophosphoric acid. The flow rate was set at 1.0 mL/min, and detection of the effluents occurred at 250 nm. Results: The retention time for Lobeglitazone was determined to be 2.157 min. The drug exhibited linearity within the concentration range of 10-60 µg/mL, the correlation coefficient was established to be 0.9996. The LOD, LOQ were found to be 0.8 µg/mL and 2.5 µg/mL. The accuracy of the method was considered satisfactory and the mean recovery percentage is found to be in the acceptable range of 99.78-101.31%. Conclusion: The HPLC method was successfully developed, validated as per ICH guidelines. The proposed method was simple, precise, sensitive, rapid, robust for the estimation of Lobeglitazone in both bulk and tablet dosage forms. [ABSTRACT FROM AUTHOR]

The aims of research is to develop and validates appropriate ultraviolet spectroscopy and reverse phase high performance liquid chromatography method for analyzing Emtricitabine in a dosage form which are accurate, sensitive and reproducible methods. For the ultraviolet spectroscopy we use wavelength of 280 nm using methanol as solvent and we also validate parameters such as linearity, accuracy, limit of detection, limit of quantification were studied, similarly for reverse phase high performance liquid chromatography method we using methanol (high performance liquid chromatography grade):water (high performance liquid chromatography grade) in the ratio of (60:40) and various validation parameters are evaluated for Emtricitabine by reverse phase high performance liquid chromatography which are determined according to International Council for Harmonization Q2B guidelines. Both the regression coefficient (r2) was found to be 0.99 and 0.99 for ultraviolet and reverse phase high performance liquid chromatography respectively. The proposed method are effective, highly sensitive, precise and accurate and hence used for determination of Emtricitabine. [ABSTRACT FROM AUTHOR]

Objectives: The current study goal was to create a precise, sensitive, and validated reverse phase-high performance liquid chromatography (RP-HPLC) method for assessing the direct-acting antiviral daclatasvir (DCV) as well as to evaluate the stability of DCV in both drug and tablet formulations. The current investigation was to display stability indicating methods under different stress conditions, including hydrolysis (acidic, basic, and neutral), oxidation, and photolysis. Materials and Methods: All experiments were performed on HPLC Agilent 1100 with a stainless steel Hypersil C18 column having a particle size of 5 µm and a dimension of 4.6 x 250 mm. The mobile phase chosen was acetonitrile: 0.05% o-phosphoric acid (50:50 v/v) in isocratic mode with 0.7 mL/min flow rate and wavelength 315 nm was selected for detection. Results: This method was validated for linearity and range, accuracy, precision, limit of detection, limit of quantification, and robustness in accordance with International Council for Harmonisation (ICH) requirements. The results were satisfactory. It was observed that retention time (tR) was 3.760 ± 0.01 min. In acidic conditions, DCV degradans show tR at 3.863, 4.121, and 4.783 min and tandem mass spectrometry (MS/MS) spectra scans had m/z 339.1, 561.2 fragment ions. In basic condition, DCV degradans show tR at 5.188, 5.469 min and MS/MS spectra scans having m/z 294.1, 339.1, 505.2, 527.2 fragment ions. In oxidation conditions, DCV degradans shows tR at 4.038 min and MS/MS spectra scans having m/z 301.1 and 339.1 fragment ions were observed. Conclusion: All the mass fragments exhibited additional degradation observed for different stress conditions. This will help to identify the structure of the degradant and its pathways. No degradation was observed in neutral and photolytic conditions. [ABSTRACT FROM AUTHOR]

Introduction: An accurate, simple, precise, rapid, economic and reproducible reverse-phase high-performance liquid chromatography method was developed and validated for the estimation of Esomeprazole (ESO) in bulk and tablet dosage form. Method: The separation was carried out on Finepak SIL C18T-5 column (250 × 4.6 mm, 5.0 µm i. d.) using potassium dihydrogen phosphate buffer (0.025M): ACN (20:80 v/v) and at a flow rate of 1.0 mL/min. using UV detector at 302 nm with a run time of 10 min. The method was validated for accuracy for linearity, accuracy, precision, limit of detection (LOD), limit of quantification (LOQ) and robustness. Results: The standard calibration curve was linear with R² = 0.995. LOD and LOQ obtained for esomeprazole were 0.0001 and 0.0004 µg/mL respectively. The method was found robust for possible changes. Results of analysis of other parameters were also tested and validated as per ICH guidelines and recovery studies confirmed the accuracy of the proposed method. validation studies showed that the developed HPLC method is simple, reproducible, rapid, precise and reliable. The high recovery and low relative standard deviation confirm the suitability of the developed method for the determination of esomeprazole in the tablet dosage form. Conclusion: This method may be used as a more convenient and efficient option for the analysis of esomeprazole to establish the quality of the substance during routine analysis with consistent and reproducible results. [ABSTRACT FROM AUTHOR]

The development and validation of an easy and rapid stability-indicating RP-HPLC technique for Tenofovir alafenamide and its impurities. In this newly developed method, chromatographic separation of Tenofovir alafenamide and its impurities was achieved on an Inertsil ODS-3V C18 (250 mm x 4.6 mm, 5 μ) column. The impurities were extracted by a mixture of Mobile Phase A: buffer solution: Acetonitrile: Purified water (20:02:78) and Mobile Phase B: Solvent Mixture and Purified water (75:25), The injection volume was 20 μL, the column temperature was 40°C, the flow rate was 1 mL/min, and the detection was carried out at 262 nm. The retention time of Tenofovir alafenamide, PMPA, PMPA anhydrate, Phenyl PMPA and PMPA isopropyl alaninate were 56.24, 5.69, 8.71, 25.89 and 37.13 respectively. The Correlation Coefficient within the acceptance criteria is not less than 0.999. The evaluated concentrations for Tenofovir alafenamide and its impurities were in the range of 0.5–7.5 ppm. The average recovery value was in the range of 90.2–113.9%. Tenofovir alafenamide's LOD and LOQ were determined to be 0.1 μg/mL and 0.5 μg/mL respectively. Tenofovir alafenamide solution degradation behaviour was assessed using solution stability studies. A new, accurate, and precise method has been developed, evaluated, and elevated for the detection of impurities in Tenofovir alafenamide tablet dosage form. The results obtained from the validation study established that this method is specific, reliable, precise and effective. As a result, the proposed strategy can serve as an alternate method to determine related substances in routine analysis of tablet dosage form. [ABSTRACT FROM AUTHOR]

A simple and selective reversed-phase high performance liquid chromatography method was developed and validated for the quantification of 4-chloroaniline, 2-chloro-N-(4-chloro-2-(2-chlorobenzoyl)phenyl)acetamide and 2-iodo-N-(4-chloro-2-(2-chlorobenzoyl)phenyl)acetamide in lorazepam. 4‑Chloroaniline is used as a raw material and 2-chloro-N-(4-chloro-2-(2-chlorobenzoyl)phenyl)acetamide and 2-iodo-N-(4-chloro-2-(2-chlorobenzoyl)phenyl)acetamide are formed as intermediates in the synthesis of anxiety disorder active pharmaceutical ingredient lorazepam. This method provided excellent sensitivity and a typical target analyte level of 150 ppm. This method was developed on an Agilent poroshell 120 EC-C18 (100 × 4.6 mm, 4 µm) column and a photo diode array detector. The proposed method is specific, linear, accurate and precise. The calibration curve was linear over the concentration range of LOQ to 120% with a correlation coefficient of 0.99. This method has low limits of detection and quantification for all the analytes. Accuracy was observed within the range of 85–115% for all the analytes. The developed method was validated as per the ICH guidelines in terms of specificity, precision, limit of detection, limit of quantification, linearity range and accuracy. [ABSTRACT FROM AUTHOR]

A new accurate LC-MS/MS methodology was needed for the simultaneous quantitation of remogliflozin etabonate and metformin in plasma samples. Chromatography was executed with BDS-Hyoersil, C18 (50mm×4.60mm, 5.0µ) reverse phasic analytical stationary system with movable solvent comprising of 0.10% HCOOH, methyl alcohol, and acetonitrile in the fraction of 10:45:45. Multiple reaction monitoring exhibits ionic conversions at m/e 130.14 85.08, m/e 523.26 271.18 and 586.19 57.07 for Metformin (MTF), Remogliflozin etabonate (RME), Fosamprenavir internal standard (IS) correspondingly. Method recovery outcomes were not less than 90%, and findings of accuracy values were within the relative error of ±6.0%. MTF has a mean Tmax of 5.62 ± 0.22. AUC0last was 374.86 ± 9.889 and Cmax was 1.89 ± 1.23 for the sample. RME has a mean Tmax of 52.99 ± 0.12. AUC0last was 265.83± 9.81 and Cmax was 41.13 ± 0.97 for the sample. [ABSTRACT FROM AUTHOR]

While histone deacetylase inhibitors, such as vorinostat, demonstrate a significant effect against hematological cancers, their application for solid tumor treatment is limited. However, there is strong evidence that combinatorial administration of vorinostat and genotoxic agents (e.g., doxorubicin) enhances the antitumoral action of both drugs against tumors. We developed a high‐performance liquid chromatography method for the simultaneous determination of doxorubicin and vorinostat in polymeric nanoparticles designed to provide the parenteral administration of both drugs and increase their safety profile. We performed separation on Nucleodur C‐18 Gravity column with a mixture of 10 mM potassium dihydrogen phosphate buffer pH 3.9:ACN (90:10 v/v) as mobile phase at 240 nm. The method was linear within the concentration range of 4.2–52.0 μg/ml for both drugs with limits of detection and quantification of 3.5 and 10.7 μg/ml for doxorubicin and 2.5 and 7.7 μg/ml for vorinostat, respectively. The method was precise and accurate over the concentration range of analysis. Drug loading was 5.4% for doxorubicin and 0.8% for vorinostat. Degradation of doxorubicin after irradiation was less than 5%, while the amount of vorinostat decreased at 88% under the same conditions. Thus, the validated method could be adopted for routine simultaneous analysis of doxorubicin and vorinostat in polymeric nanoparticles. [ABSTRACT FROM AUTHOR]

Chlorin e6 and curcumin are often used in the treatment of various cancers, including breast, skin, colon, and lung cancer. The present objective of this study is to develop a simple, sensitive, precise, and selective reversed‐phase high‐performance liquid chromatography analytical method for the estimation of curcumin and chlorin e6. Curcumin and chlorin e6 are both estimated simultaneously in bulk and on nanocarriers based formulations. The efficient chromatographic separation of chlorine e6 and curcumin was obtained using SUPELCO C‐18 column with a mobile phase containing ACN and water (pH 2.6 adjusted with trifluoracetic acid 0.1%) in an isocratic mode at a detection wavelength of 412 nm. The flow rate and column oven temperature were kept at 1 ml/min and 30°C, respectively. The retention times for curcumin and chlorin e6 were found to be 11.7 and 13.5 min, respectively. The simultaneous technique was used to estimate the %drug entrapment efficiency, drug loading, as well as the cumulative percentage of drug release of chlorin e6 and curcumin in‐house designed nanoformulations. %Drug loading and entrapment efficiency were found to be 2.22% and 79.92% for curcumin, while 2.43% and 89.47% for chlorin e6, respectively. [ABSTRACT FROM AUTHOR]

The main objective of proposed method is to develop, validate & to perform the forced degradation studies for the simultaneous quantification of lamivudine, doravirine and tenofovir in active pharmaceutical ingredient (API) and formulation using reverse phase ultra-performance liquid chromatography (RP-UPLC). The estimation was performed using HSS C18 (100mm×2.1mm, 1.8µ) column with acetonitrile and 0.1% ortho phosphoric acid (OPA) (35:65) as mobile phase ran in isocratic mode at rate of flow 0.3 mL/minute. The column temperature maintained at 30°C and detection wavelength used was 260nm. The developed method validated as per ICH guidelines. Method obeyed Beer's law in the range of concentration of 37.5 µg/mL-225 µg/mL, 37.5 µg/mL-225 µg/mL and 12.5 µg/mL-75 µg/mL for lamivudine, tenofovir and doravirine respectively. The method is stable when exposed to different stressed conditions with less degradation. For regular analysis of estimate of lamivudine, tenofovir, and doravirine in tablet formulation, this UPLC method can be employed. [ABSTRACT FROM AUTHOR]

A simple, sensitive, accurate and inexpensive UV-reversed-phase high-performance liquid chromatographic method was developed for the determination of ascorbic acid in tablet formulations. The method was based on the separation of ascorbic acid using a mobile phase of an acetonitrile-NaH2PO4-H3PO4 buffer solution (pH = 3) (5:95 v/v) with a UV detection wavelength of 245 nm and a flow rate of 0.8 mL min−1 at ambient column temperature. The variables of the proposed method, such as acetonitrile fraction (%), flow rate (mL min−1) and column temperature (°C), were optimized on the peak area by response surface methodology via the Box–Behnken design. The mobile phase was passed isocratically, and the separation of ascorbic acid was performed at the retention time of 4.1 min. A calibration graph was obtained and found to be linear in the concentration range of 10–180 µg mL−1. The method suitability was assessed and an asymmetry factor of 1.15 was obtained. The proposed method was successfully applied for the determination of ascorbic acid in tablet formulations and statistically compared with the results of the reference method. The performance of the proposed method was excellent and in agreement with the reference method. The recovery percentage of the proposed and reference methods was in the range of 99.98–100.04% and showed compliance (100 ± 2%) with regulatory guidelines. [ABSTRACT FROM AUTHOR]

New stability indicating RP-HPLC method for the simultaneous estimation of sofosbuvir and daclatasvir in its pharmaceutical dosage form was developed and validated. Column used was PhenomenexC18 (150mm x 4.6mm, 5µ) with mobile phase water and acetonitrile (50:50 V/V) in isocratic mode. Flow rate of mobile phase 1.0mL min-1 and column oven temperature were maintained at 30oC. Sofosbuvir and daclatasvir were detected at a wavelength 230nm. The retention times for sofosbuvir and daclatasvir were found to be 3.06 min and 4.76 min, respectively. Validation of the method was done according to ICH guidelines. The method was found to be accurate, precise, specific and robust. The method shows good linearity in concentration range of 50 µg mL-1 - 500 µg mL-1 of sofosbuvir and 7.5 µg mL-1 - 75 µg mL-1 of daclatasvir, with correlation coefficient of 0.999 for both the drugs. The drugs as well as their degradation products produced in stress study were separated using this developed method. [ABSTRACT FROM AUTHOR]

The present work reports a validated reverse phase-HPLC method for determination of nortriptyline hydrochloride (NORH) in bulk and in its pharmaceutical dosage form. Chromatographic separation was performed on Waters C-18, (250×4.6mm, 5µm) stationary phase using a mixture of 50 mM KH2 PO4 pH 3.0 phosphate buffer: methanol: acetonitrile in the proportion of 50: 10: 40 V/V/V as mobile phase components at 1.0 mL min-1 flow rate. Detection of drug was carried out in isocratic mode at 235 nm. The validation of the method was carried out as per ICH guidelines. The LOD and LOQ for NORH was 0.22 µg mL-1 and 0.69 µg mL-1, respectively. NORH showed linearity range of 5-50 µg mL-1 and correlation coefficient (r² ) value, 0.9937. The method was tested for assay of NORH in tablet dosage form. [ABSTRACT FROM AUTHOR]

A simple, rapid, accurate and precise isocratic reversed phase high performance liquid chromatographic method has been developed and validated for simultaneous estimation of Decitabine and Cedazuridine in tablet dosage form. The chromatographic separation was carried out on Zorbax C18 column (150 mm x 4.6 mm I.D., 5 μm particle size) with a mixture of 0.01N potassium dihydrogen phosphate buffer and acetonitrile in the ratio of 65:35% v/v as a mobile phase at a flow rate of 1.0 mL/min. UV detection was performed at 245 nm. The retention times were 2.263 minutes and 3.001 minutes for Decitabine and Cedazuridine respectively. Calibration plots were linear (r²=0.999 for both Decitabine and Cedazuridine respectively) over the concentration range of 8.75-52.5 μg/mL for Decitabine and 25-150 μg/mL for Cedazuridine. The method was validated for linearity, precision, accuracy, ruggedness and robustness. The proposed method was successfully used for simultaneous estimation of Decitabine and Cedazuridine in tablet dosage form. Validation studies revealed that the proposed method is specific, rapid, reliable and reproducible. The high % recovery and low % RSD confirms the suitability of the proposed method for routine quality control analysis of Decitabine and Cedazuridine in bulk and tablet dosage form. [ABSTRACT FROM AUTHOR]

A method for the determination of amizone and amixin in the same sample and in their mixture with antibiotics (ceftriaxone, tetracycline, ampicillin and levofloxacin) was developed using reversed-phase highperformance liquid chromatography equipped with a photodiode array detector. A SunFire C18 column, a mobile phase consisting of sodium perchlorate buffer (pH = 2.5) and acetonitrile (75:25), at a flow rate of 0.8 ml/min, was used. The analytes were identified at 205 and 265 nm. The specificity, linearity, precision parameters, LOD and LOQ were evaluated during the validation of the methodology, and the correlation coefficients of amizone and amixin were 0.9992 and 0.9998, respectively. This method can also be used for the determination of amizone and amixin and their presence in a mixture with antibiotics in the environment. [ABSTRACT FROM AUTHOR]

In this study, a new high performance liquid chromatography (HPLC) analysis method was developed for the simultaneous determination of flurbiprofen (F) and thiocolchicoside (T) in pharmaceutical products. A C18 column (Agilent Poroshell 120 EC-C18) was used as the stationary phase. Elution of the analytes was achieved by using gradient elution system. Mobile phase A was an acetate buffer (100 mM, pH 4.8) and mobile phase B was acetonitrile. The flow rate for the method developed was 0.5 ml/min. The temperature of the column compartment was set at 40°C and the injection volume was 5 µl. Monitoring of the analytes was carried out at 248 nm. The method was found linear in the concentration range between 5-100 ppm. The correlation coefficient value was calculated as 0.999 for F and 0.999 for T. The method was found suitable in terms of accuracy, precision, specificity, linearity, and robustness ruggedness. Furthermore, it was applied successfully for the analysis of commercial tablets and gel samples that contains F and T without any time-consuming pre-procedure. The recovery values for Fand T were found as 99.5% and 97.0% in tablet formulations and 98.6% and 99.3% in gel formulations, respectively. All results were acceptable and this confirmed that the method is suitable for its intended use in routine quality control and an assay of drugs. [ABSTRACT FROM AUTHOR]

Objectives: To develop a simple, rapid, reliable and precise RP-UPLC method for the simultaneous estimation of lamivudine, didanosine and efavirenz in bulk and its tablet dosage forms. Materials and Methods: The chromatographic separation was achieved by using Zorbax SB Cyano (150x4.6mm ID) 1.7µm column, isocratic mobile phase consists; Ammonium acetate Buffer pH 4.5: Acetonitrile (55:45) %v/v with a flow rate of 1.0 ml/min. The detection was carried out at 274 nm. The current method was validated according to the ICH guidelines for accuracy, precision, linearity, specificity, robustness and ruggedness. Results: The retention times obtained for lamivudine, didanosine and efavirenz were 2.584, 4.228 and 5.206 min respectively. The calibration curves of peak area versus concentration, were linear from 15-45µg/mL, 30-90µg/mL and 20-60µg/mL for lamivudine, didanosine and efavirenz and had regression coefficient (R2) 0.999. Limit of detection were found to be 1.7, 3.3, 3.8 µg/ml and limit of quantification were found to be 5.1, 6.7, 11.5 µg/ml respectively for lamivudine, didanosine and efavirenz. The % assay of the marketed dosage form was found to be 100.2, 100.4 and 100.6 for lamivudine, didanosine and efavirenz. Conclusion: The experimental study results revealed the suitability of proposed method that can be used for simultaneous estimation of lamivudine, didanosine and efavirenz in bulk and their pharmaceutical formulations for routine quality control analysis. [ABSTRACT FROM AUTHOR]

The objective of the study was to develop reverse phase high performance liquid chromatography method for the determination of purity of ondansetron and pantoprazole in tablet form. A reverse phase high performance liquid chromatography method was developed for the estimation of ondansetron and Pantoprazole in tablet formulation. The current method consists of different mobile phase compositions and it is a new approach for the estimation of selected drugs in quality control laboratory, which is novel to the market and for better illusion, buffer was used in the present method. Chromatographic separation of the drug was achieved on a Phenomenex Kromosil C-18, 5 µm, column (250×4.6 mm) using a mobile phase of methanol: Acetonitrile: Potassium hydrogen ortho phosphate buffer pH 3 (40:20:40 v/v) at a flow rate of 1 ml/min. The drug eluted was monitored at 210 nm and the retention time of ondansetron and pantoprazole was found to be 2.7 and 4.l min respectively. The calibration curve was linear over the range of 20-120 µg/ml. The correlation coefficient was found to be 0.999 and 0.998 for ondansetron and pantoprazole respectively. The limit of detection and limit of quantification were found to be 0.075 µg/ml and 0.232 µg/ml for ondansetron and 0.063 and 0.219 for pantoprazole which was within the acceptance range. Forced degradation was carried out under various stress conditions to demonstrate the stabilityindicating capability of the developed reverse phase high performance liquid chromatography method. The performance of the method was validated according to International Council for Harmonization guidelines. The proposed method was found to be simple, precise, accurate and validated according to the International Council for Harmonization guidelines. [ABSTRACT FROM AUTHOR]

Objectives: A precise, accurate and selective stability-indicating reverse phase high performance liquid chromatographic assay method has been developed for the simultaneous quantitative determination of Tolperisone hydrochloride and Etoricoxib in tablets. Methods: The chromatographic separation of drugs was attained by using Eclipse plus C18 (150 mm x 4.6 mm, Agilent 5µm) column at room temperature. The composition of mobile phase was mixture of 0.035M triethylamine (pH 3.0 adjusted with orthophosphoric acid) and acetonitrile in ratio of 70:30 v/v and flow rate of mobile phase 1.0 ml/min with isocratic elution. The signal of eluents was observed at 290 nm by using diode array detector. Results: The retention time of Tolperisone hydrochloride and Etoricoxib were found to be 2.826 min and 7.566 min, respectively. The linearity ranges for both drugs were found to be 5-15 μg/ml and the percent recoveries were found to be 99.39% and 99.15% for Tolperisone hydrochloride and Etoricoxib respectively. Various forced degradation conditions, such as alkali hydrolysis, acid hydrolysis, thermal degradation, photolytic degradation, and oxidative degradation, were applied to the drug ingredients and drug formulation. The degradants were efficiently separated from the drugs by using optimized chromatographic conditions. The developed method was validated as per recommendation parameters of International council on harmonization guidelines Q2(R1). Conclusion: The validation parameters indicate that the drug substances were efficiently separated from its degradants and developed method can be routinely applied for the simultaneous quantitative determination of Tolperisone hydrochloride and Etoricoxib in combined tablet formulation in the quality control laboratory. [ABSTRACT FROM AUTHOR]

Background: The present work is focused on developing a simple stability indicating method for the estimation of the assay of benzyl alcohol and glycopyrrolate in glycopyrrolate injection using reverse high performance liquid chromatography. Methods: A simple, selective, rapid, precise, and gradient reversed-phase high-pressure liquid chromatography procedure has been proposed to estimate the assay of benzyl alcohol and glycopyrrolate for glycopyrrolate injection. It was developed on a Kromasil 100-5, C8 250 mm x 4.6 mm, 5 µm column using mobile phase-A, containing pH 2.5 potassium dihydrogen phosphate buffer and methanol in a ratio of 80:20 v/v. and mobile phase-B, containing pH 2.5 potassium dihydrogen phosphate buffer and methanol in a ratio of 10:90 v/v at a flow rate of 1.5 mL/min. The detection of glycopyrrolate and benzyl alcohol was carried out at 222 nm and 254 nm. A sharp peak was obtained for glycopyrrolate and benzyl alcohol at a retention time of about 8.4 and 4.8 min. Results: The method was validated for specificity (blank, system suitability solution, standard, and sample and stress samples for any interference), precision (six replicate sample preparations), robustness (by slightly varying critical method parameters), and solution stability, and the results were found satisfactory. Conclusion: The method is specific, precise, accurate, and robust for estimation of the assay of benzyl alcohol of glycopyrrolate in glycopyrrolate injection. [ABSTRACT FROM AUTHOR]

A simple, rapid isocratic reverse phase high performance liquid chromatography method was developed and validated for the determination of pramipexole dihydrochloride in tablet dosage form as per International Council on Harmonisation guidelines. In this method the chromatographic separation was carried out using C18 column with ultraviolet detector set at 264 nm. The eluent consisted of acetonitrile:phosphate buffer (pH 4.0) (70:30 by volume) with a flow rate of 1 ml/min. The method showed linear response with the retention time of 2.28 min. The main advantage of the developed method is its cost effectiveness and shortened run time. Hence this method can be applied for routine analysis of pramipexole in pharmaceutical dosage form. [ABSTRACT FROM AUTHOR]

A rapid and simple liquid chromatographic method was developed for the quantitative determination of dexrabeprazole sodium in the tablet dosage form. The reverse-phase chromatographic analysis was carried out by using a C-18 column. The acetonitrile-phosphate buffer mixture was used as the mobile phase. The obtained retention time was 4.33∓0.02 min. by using 50:50 (v:v) acetonitrile:phosphate buffer(pH 7) and 1.0 mL/min. flow rate. Quantification of the analyte was based on measuring the peaks areas at 272 nm. The analytical performance of the developed RP-HPLC method was validated with respect to accuracy, precision, linearity, stability, and robustness. The obtained linearity range was 77-143 mg/L and the correlation coefficient was 0.9989. The obtained LOD and LOQ values were 0.010 mg/L and 0.034 mg/L, respectively. [ABSTRACT FROM AUTHOR]

Favipiravir (FVP), a pyrazine analog, has shown antiviral activity against a wide variety of viruses. It is considered to be worth further investigation as a potential candidate drug for COVID-19. It is not officially available in any pharmacopoeia. A rapid, simple, precise, accurate, and isocratic high performance liquid chromatography (HPLC) method has been developed for routine quality control of favipiravir in pharmaceutical formulations. Separation was carried out by C18 column. The mobile phase was a mixture of 50 mM potassium dihydrogen phosphate (pH 2.3) and acetonitrile (90:10, v/v) at a flow rate of 1 mL min−1. The ultraviolet (UV) detection and column temperature were 323 nm, and 30 °C, respectively. The run time was 15 min under these chromatographic conditions. Excellent linear relationship between peak area and favipiravir concentration in the range of 10–100 μg mL−1 has been observed (r2, 0.9999). Developed method has been found to be sensitive (limits of detection and quantification were 1.20 μg mL−1 and 3.60 μg mL−1, respectively), precise (the interday and intraday relative standard deviation (RSD) values for peak area and retention time were less than 0.4 and 0.2%, respectively), accurate (recovery, 99.19–100.17%), specific and robust (% RSD were less than 1.00, for system suitability parameters). Proposed method has been successfully applied for quantification of favipiravir in pharmaceutical formulations. [ABSTRACT FROM AUTHOR]

Objectives: This study was aimed to develop and validate the use of reverse-phase high pressure liquid chromatographic method for the estimation of simvastatin (SIM) and mupirocin (MUP) simultaneously. Materials and Methods: The chromatographic method developed is optimized for flow rate with the column, solvent, and buffer used and mobile phase ratio, molarity, and pH. The validation of the optimized method and the forced degradation studies of both drugs (under acidic, alkaline, oxidation, heat, light, and neutral conditions) were conducted following the The International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use guidelines. Results: Kromasil C18 column (250 mm × 4.6 mm, 5 µm) with ultraviolet detection at 224 nm and acetonitrile/phosphate buffer (30 mM, 70:30 v/v, pH 3.5; adjustment done using orthophosphoric acid) as mobile phase at a flow rate of 1.1 mL/min were observed to provide a good resolution for MUP and SIM at retention times of 2.32±0.008 and 13.55±0.254 min, respectively, with high accuracy (percent recovery was 99.69±0.82 for MUP and 101.10±0.02 for SIM) and linearity in the range of 5-30 µg/mL (r²: 0.9969 for MUP and r²: 0.9959 for SIM). The diagnostic limit and the lower limit of determination were 0.771±0.234 and 2.338±0.246 μg/mL for MUP and 0.595±0.282 and 1.803±0.334 µg/mL for SIM, respectively. The validated method was used to understand the degradation behavior of both drugs after the forced degradation studies. Conclusion: The analytical method developed is determined to be specific, sensitive, precise, and accurate for the estimation of MUP and SIM simultaneously in the combined dosage form. [ABSTRACT FROM AUTHOR]

A straightforward, exact, fast and affordable reverse phase fluid chromatographic strategy has been produced for the assessment of fosamprenavir in mass and in tablets, utilizing versatile stage containing 20mM Ammonium acetate buffer (pH-3.0) and acetonitrile [50:50 %v/v] at a stream pace of 1.0ml/min. An Phenomenex Luna C18 (250 x 4.6mm i.d, 5µ) column was utilized as a stationary phase. Quantitation was performed utilizing diode exhibit identifier at 225nm and the run time noticed was 4.0min. The retention time of the medication was discovered to be 1.598min. The linearity was seen in the scope of 5.0-15μg/ml with connection coefficient 0.9974. The rate measure of fosamprenavir was 99.5 to 101.2%.The created technique was approved to decide its exactness and accuracy via completing recuperation considers and intra-day and between day examines. Consequently, the current strategy is basic, exact, precise and fast for the assessment of fosamprenavir in tablet measurement structure. [ABSTRACT FROM AUTHOR]

For the treatment of diabetes mellitus, a new formulation containing remogliflozin etabonate (REMO) and metformin HCl (MET) has recently been approved. This study is aimed to develop simple and quick RP-UHPLC methods for measuring REMO and MET simultaneously. REMO and MET chromatographic separation were carried out on a Zorbax Eclipse Plus C18 (150×4.6 mm, 5 µm) column with acetonitrile: phosphate buffer (pH: 3) (60:40 %, v/v) mobile phase, 10 µl sample volume and 1.0 ml/min flow rate at 230 nm in a diode array detector. REMO had a 99.51 % average percent assay, while MET had a 99.60 % average percent assay. The methods projected were simple, precise, accurate, and fast. They can also be used to verify the consistency of REMO and MET formulations regularly. [ABSTRACT FROM AUTHOR]

A specific, accurate, precise, and reproducible liquid chromatographic method has been developed and validated for the estimation of acamprosate calcium and baclofen in combination. The separation was achieved using stationary phase Phenomenex C18 column (150 mm× 4.6 mm.) in isocratic mode, with mobile phase containing 0.05 M potassium dihydrogen orthophosphate buffer (pH 7): acetonitrile (10:90 V/V), at a flow rate of 1.0 mL/min and effluents were monitored at 210 nm. The retention time of acamprosate calcium and baclofen were found to be 1.9 min and 5.3 min, respectively. The linearity for acamprosate calcium and baclofen were in the range of 2-64 µg/mL and 1.2-38.4 µg/mL, respectively. The method was validated as per ICH guideline. The recoveries of Acamprosate calcium and baclofen were found in the range of 98.90 - 100.13 % and 98.60 -100.02 %, respectively. The method was successfully applied for the determination of both the drugs in combination. [ABSTRACT FROM AUTHOR]

For determination of eliglustat tartrate, a new, specific, simple, accurate (recovery) and precise stability-indicating HPLC method has been developed and validated according to ICH Q2(R1) guidelines. The HpLC method was developed using acetonitrile: 0.1 % orthophosphoric acid 40:60 (V/V) as mobile phase, with pH of mobile phase adjusted to 3.0. The column used was HiQSil C-18 (250 mm x 4.6 mm, 5 pm) as stationary phase at a flow rate of 0.7 mL min-1. Retention time for eliglustat tartarate was found to be 5.9 min. The eluted compounds were detected using a PDA detector. The drug was subjected to stress testing as per ICH Q1A (R2) guideline. The degradation products did not interfere with the retention time of eliglustat. The calibration curve was found to be linear over a concentration range of 10-50 μg mL-1. For the calibration plots, R² was found as 0.9995, indicating good linear relationship. The accuracy of the developed method was in the range of 99.87-100.62 %. The limit of detection of eliglustat was found to be 0.23 μg mL-1 and limit of quantification was 0.68 μg mL-1. [ABSTRACT FROM AUTHOR]

Validated analytical methods must be used for accurate and precise determination of identity, purity, strength, and quality of any pharmaceutical dose intended for human administration. Consequently, all analytical methods must be validated per USP <1225> and the ICH Q2R1 guidelines to meet the cGMP requirements of the FDA and EMA. A reversed-phase high-performance liquid chromatography analytical method, with <10 min run time, was developed for the analysis of [11C]nicotine. The analytical method was found to be specific, accurate, suitable, robust, precise, and linear for [11C]nicotine, nicotine, and (±) nornicotine in the concentration ranges studied. The LOD and LOQ values were also established. [ABSTRACT FROM AUTHOR]

In present study, a novel, simple, robust, stability-indicating, highly sensitive and specific reverse phase ultra-performance liquid chromatographic method was established and validated for the determination of ibrutinib using acquity charged surface hybrid C-18 (100 mm×2.1 mm, 1.7 µm) column with a mobile phase consisting of mixture of Eluent-A phosphate buffer, 0.1 % triethylamine, (pH 6.0) and Eluent-B acetonitrile with flow rate 0.3 ml min-1. The detection was monitored at 215 nm using photodiode array detector. Linearity was observed from 25 to 250 ng ml-1 (correlation of coefficient was 0.9999) with equation, y=100.1880x-130.8966. The observed limit of detection and limit of quantitation were 25 ng ml-1 and 50 ng ml-1 respectively. Ibrutinib was subjected to stress conditions comprising hydrolytic (acid, alkali and neutral), oxidative, photolytic and thermal degradation as per International council for harmonisation Q1 guidelines. The results showed that substantial degradation were observed in acid, base and peroxide degradation condition and resistant to neutral, photolytic and thermal degradation. This is first highly sensitive stability-indicating ultra-performance liquid chromatography method capable of separating ibrutinib and its ten degradation products at nano gram (ng) level. The method was validated as stated by International council for harmonisation guidelines. [ABSTRACT FROM AUTHOR]

A novel, simple, selective, rapid stability-indicating and LC-MS compatible short run time UPLC method was developed and validated for the determination of afatinib and its related substances in bulk and finished dosage form. A reverse phase gradient mode short run time method has been developed by using UPLC to separate all the five known impurities of Afatinib. The chromatographic separation of afatinib and its related impurities was achieved by using Acquity UPLC HSS PFP column 100*2.1 mm, 1.8 µm using 0.1% V/V formic acid in milli-q water and acetonitrile as a co-solvent with a run time of 12 minutes. The column temperature was maintained at 30°C. The mobile phase flow rate was 0.4 mL/min and the UV detection was carried out at a wavelength of 258 nm. The proposed method was validated in terms of specificity (forced degradation), linearity, accuracy, precision, robustness and ruggedness as per ICH quality guidelines Q2 (R1). Forced degradation was performed using hydrolysis, oxidation, thermal and photolytic conditions with good resolution between degradants and analyte. Degradation peaks neither co-elute with the main analyte nor with the known impurities, indicating that the proposed method as is stability indicating. Limit of quantification for all the five known impurities and analyte were in the range of 0.02 ppm to 0.05 ppm, indicating that the method is sensitive. Recovery of the impurities and analyte at various levels ranging from LOQ level to 200% level was in the range of 96.9 to 101.8%, indicating that the method was accurate and precise. Hence the validated method can be successfully applied for the quantitative estimation of afatinib and its related impurities in bulk and tablet dosage form. [ABSTRACT FROM AUTHOR]

Levofloxacin (LFX) is a fluoroquinolone antibiotic, which so far, has no method of determining its level in urine using solid-phase extraction (SPE) technique followed by quantification with high-performance liquid chromatography (HPLC) with a UV-Vis detector. The purpose of this study is to find a selective and fast method for examining levofloxacin in the urine. This analysis used a high-performance liquid chromatography method, using a C18 inverse phase column, the stationary phase (column) used was octadecyl silane (ODS) 250 x 2.6 mm, 10 μm particle size, using a mixture of phosphate buffer: acetonitrile (85.5: 14.5, v/v) pH 2.5 as a mobile phase, with a flow rate of 1.2 mL/min and using ciprofloxacin (CFX) as internal standard (IS). Levofloxacin was detected at a wavelength of 295 nm using a UV detector with a levofloxacin retention time of 9–10 minutes and a resolution of 1.7 from urine. Linearity was obtained by using the internal standard of ciprofloxacin 10 μg/mL with a concentration of levofloxacin 1.15, 2.8, 5,75, 11.5, and 23 μg/mL, the correlation coefficient (r) = 0.999. The limit of detection (LOD) of levofloxacin and limit of quantitation (LOQ) and were 0.0733 μg/mL and 0.0220, respectively. The percent recovery based on an area of 1.15 and 23 μg/mL was 106.84% and 89.37%, based on the peak height of 109.52 μg/mL and 91.90 μg/mL, relative standard deviation (RSD) precision (%) respectively 1.09% and 0.45% based on area and based on peak heights of 12.66% and 1.13%. The concentration accuracy value of 1.15, 5,75, and 23 μg/mL were 86.23%, 99.98%, and 97.95% while the precision was 2.78%, 5.27%, and 1.14%. The results of the system suitability test and repeatability to retention time, area ratio, and peak height showed coefficient variation RSD <15%. The results of the validation method meet the requirements so that it can be used to determine levofloxacin in the urine for routine analysis [ABSTRACT FROM AUTHOR]

Nanotechnology has surmounted various application in drug delivery despite divergent challenges in physical, surface properties and reproducibility of preparation method. Ultrasensitive analytical methods are highly demanded in order to monitor the very minute drug concentrations obtained during drug release studies as a result of the extensive prolongation in the release rate achieved in all nano-particulate drug delivery systems. A simple, rapid, sensitive, reversed-phase isocratic RP-HPLC method for determination of valsartan (Val) was developed. The method was applied for quality control tests including entrapment efficiency and drug release for Val-loaded nano-structured lipid carriers (NLC). The method was carried out using Eclipsed XBD column (Agilent -PN 993967) C18 (150 mm x 3.0, 5μm particle size) with mobile phase composed of acetonitrile: phosphate buffer (60:40) at pH 3.6, 0.01 M. The flow rate was set at 1.0 ml/min and effluent was detected at 273nm. The retention time of valsartan was found to be 2.910 minute. The method was validated for specificity, accuracy, precision, linearity, and limit of detection, limit of quantification and robustness. Limit of detection (LOD) and limit of quantification (LOQ) were found to be 6.0 and 25 ng/ml respectively. The calibration curve was linear in the concentration range of 39.06-2500 ng/ml with coefficient of correlation 0.9992. The percentage recovery for Val was found to be 99.86-100.06 and the % RSD was found to be less than 2%. The proposed method was free from any interference and successfully applied for quantitative determination of valsartan in lipidbased nano-particulate systems. [ABSTRACT FROM AUTHOR]

The present work involves the development of simple, accurate, precise and stable RP- HPLC method for the estimation of Apremilast in the tablet dosage form. The method has several advantages, including simple and mobile phase, low cost solvents, rapid analysis, and simple sample preparation. In developed method, the analyte was resolved by using isocratic method and mobile phase was used Methanol: Water (80:20 v/v), at a flow rate 0.8 ml/min, the detection was carried out at 231nm. The results of analysis in the method were validated in terms of accuracy, precision, linearity, robustness. Linearity for Apremilast was found in the linear concentration range of 10-50 µg/ml with regression coefficient r2= 0.9998. The % RSD values for intra-day and inter-day precision studies were found to be less than 2%. The % recovery was found to be within an acceptable limit 98%-102%. Therefore the developed method said to be linear, precise, accurate, and robust. Since the method does not require use of expensive reagent and also less time consuming, it can be performed routinely in industry for a routine analysis of marketed product of Apremilast in tablet dosage form. [ABSTRACT FROM AUTHOR]

We developed and validated a high performance liquid chromatographic method for the simultaneous determination of a single-pill triple therapy containing: Indapamide, Amlodipine Besylate, and Perindopril. The validation parameters are tested by following the international conference of harmonization (ICH) guidelines. The three components were successfully separated in just 14 minutes. The aforementioned components were well-separated on an Inertsil C8- column (250mm x 4.6mm, 5μm) using a mobile phase prepared by mixing of Triethylamine counter ion solution (pH 3.0) with Acetonitrile at a fixed ratio of 2:1. Analysis was performed at a wavelength of 205 nm, eluent flow rate and column oven temperature was 1.5 ml/min, and 40°C, respectively. Linearity was observed in the concentration ranges of (20-30) μg/mL for Indapamide, and (80-120) μg/mL for both Amlodipine Besylate and Perindopril Arginine. We found the recovery percentages to be 99.98%, 101.04%, and 100.58% for Perindopril Arginine, Amlodipine Besylate, and Indapamide, respectively. Further, we found the detection limits to be 0.38 μg/mL, 0.99 μg/mL and 3.65 μg/mL, and the obtained quantitation limits were 1.16 μg/mL 3.01 μg/mL, and 11.06 μg/mL for Indapamide, Amlodipine Besylate, and Perindopril Arginine, respectively. [ABSTRACT FROM AUTHOR]

A revers phase liquid chromatographic technique has been developed for the separation and determination of candesartan cilexetil and amlodipine besylate using QbD (Quality by Design) approach. The present method was optimised by introducing experimental design approach to identify the chromatographic conditions for adequate separation quality and minimal analysis duration. The relation between independent variables and critical quality attributes is given by experimental design methodology. The separation was achieved on shim-pack solar C18 type column (250 mm × 4.6 mm, 5 µm) as stationary phase; acetonitrile: phosphate buffer pH 6.8 (82:18, v/v); 1.0 ml/min as flow rate; detection wavelength 235 nm. The chromatographic efficiency was investigated for the factorial effect of percentage organic phase and flow rate and finely optimized by employing factorial design experiment. The method was validated and was found to be accurate, precise and robust. [ABSTRACT FROM AUTHOR]

Fisetin (FS) is a polyphenolic phytoconstituent reported to have various pharmacological activities such as antioxidant, antiparkinsonian, and antidepressant. An analytical method was developed and validated for the estimation of FS by ultrafast liquid chromatography using C-18 reverse phase column. Acetonitrile and orthophosphoric acid (0.2% v/v) in the ratio of 30:70 v/v was used as mobile phase. Flow rate was set at 1 mL/min. Chromatogram of FS was detected at wavelength of 362 nm. Retention time for FS was found to be 7.06 min. The developed method was found to be linear in the range of 2–10 μg/mL with regression coefficient of 0.9985. The method was validated as per the International Conference on Harmonization (ICH) Q2 (R1) guidelines. The percentage recovery was in the range of 95%–105%, which indicated the accuracy of the method. The percentage relative standard deviation (RSD) was found to be <2%, which indicates the precision of the method. Limit of detection (LOD) and limit of quantification (LOQ) were found to be 0.46 and 1.41 μg/mL, respectively. The developed method was found to be robust as there was no significant change in response with change in flow rate, ratio of mobile phase, and pH. The method was successfully applied for estimation of drug loading and drug release from self-nanoemulsifying drug delivery system (SNEDDS). The % drug loading of FS in prepared liquid SNEDDS formulation was found to be 101.95%. The results of dissolution studies indicated 67.78% FS release in water at the end of 60 min. [ABSTRACT FROM AUTHOR]

Solid dispersions were prepared via a solvent evaporation method, employing ethanol (96%, v/v) as solvent, with three different polymers as carrier: povidone, copovidone, and poloxamer 407. Previously developed reversed-phase HPLC (RP-HPLC) methods were modified and used for the simultaneous determination of acetylsalicylic acid and clopidogrel bisulfate and after release from solid dispersions. Chromatography was carried out on a C-18 column, with a mobile phase of acetonitrile–methanol–phosphate buffer pH 3.0, UV detection at 240 nm, and a run time of 6 min. The method was validated according to International Conference of Harmonisation guidelines and validation included specificity, accuracy, precision, linearity, robustness, limit of detection (LOD), and limit of quantification (LOQ). The method is specific for determination of acetylsalicylic acid and clopidogrel bisulfate. The linearity was provided in the concentration range 0.0275–0.1375 mg/mL for acetylsalicylic acid and 0.0200–0.1000 mg/mL for clopidogrel bisulfate, with a correlation coefficient (R2 value) of 0.9999 for both active pharmaceutical ingredients (APIs). Accuracy was confirmed by calculated recoveries for acetylsalicylic acid (98.6–101.0%) and clopidogrel bisulfate (100.0–101.6%). The intra-day and the inter-day precision-calculated relative standard deviations are less than 1%, which indicates high precision of the method. The limits of detection and quantification for acetylsalicylic acid were 0.0004 and 0.0012 mg/mL, and for clopidogrel bisulfate 0.0002 mg/mL and 0.0007 mg/mL, respectively. Small variations in chromatographic conditions did not significantly affect qualitative and quantitative system responses, which proved robustness of method. The proposed RP-HPLC method was applied for simultaneous determination of clopidogrel bisulfate and acetylsalicylic acid from solid dispersions. [ABSTRACT FROM AUTHOR]

Aim: Azilsartan is an angiotensin II receptor blocker used in the treatment of hypertension. Using the DoE based approach in reversed-phase high-performance chromatography method was developed and validated as per ICH guidelines. Materials and Methods: The separation of Azilsartan using the Qualisil 5 BDS C18 column (250 x 4.6mm, particle size 5µ) in low-pressure gradient mode with photodiode array detector at 249nm. For optimization of chromatographic conditions for Azilsartan from its formulation with less number of experimental trials using Box-Behnken design. The critical quality attributes that are acetonitrile concentration in the mobile phase, pH of the aqueous phase and flow rate parameters were used to construct a mathematical model and study the effects of these independent factors on response such as retention time, tailing factor and theoretical plates. Analysis of Variance (ANOVA) confirmed that the three factors were significant its p-value found less than 0.05. Results: Optimized experimental conditions obtained by the DoE approach for proposed work consists of water and acetonitrile (75:25% v/v), pH 5.0 adjusted with orthophosphoric acid as a mobile phase at a flow rate 1ml/min with a retention time was found to be 3.516min. The developed method was validated as per ICH guidelines. An accuracy study was performed at three different levels and was found in the range of 98.94-100.46%. Conclusion: The method was found simple and rapid with good specificity and robustness. [ABSTRACT FROM AUTHOR]

Lifitegrast is a lymphocyte function-associated antigen-1 (LFA-1) antagonist used to treat the indications and symptoms associated with dry eye disease (DED), one of the most common ocular surface diseases. Lifitegrast has a chiral center, and the S -enantiomer (S -Lif) is responsible for the therapeutic effects, while the R -enantiomer (R -Lif) lacks efficacy in the treatment of DED. Lifitegrast ophthalmic solution containing 5% lifitegrast was approved by the United States Food and Drug Administration (FDA) in July 2016 for the treatment of DED in patients 17 years of age and older. The objective of this study was to develop a chiral HPLC method for the determination of the enantiomeric impurity of lifitegrast in the drug substance and in the ophthalmic product. In addition, we aimed to investigate the effect of stress and stability conditions on the enantiomeric purity of lifitegrast in both drug substance and ophthalmic solution. During the method development studies, four known lifitegrast impurities (Lif. Imp. A-D) and stressed lifitegrast samples were injected to ensure the specificity of the developed method. The enantiomers of lifitegrast are well separated with a resolution of higher than 4.0. They are also well separated from the peaks of the diluent, impurities, and the placebo used to prepare the ophthalmic solution without interference in 20 min. Chiral separation was achieved using a Chiralpak AD-H column (250 × 4.6 mm, 5.0 μm) at 40 °C with a mobile phase consisting of a mixture of n-hexane, 2-propanol, and formic acid (500:500:2, v/v/v) at a flow rate of 1.0 mL/min and a detection wavelength of 260 nm. Methanol was used as the diluent, and the drug substance solution was found to be stable for 48 h at 15 °C. The optimized chiral HPLC method for lifitegrast was validated according to ICH Q2, and the calibration curves showed excellent linearity for R -Lif (0.0369 – 1.816 µg/mL). This is the first stability-indicating, specific / selective, sensitive, linear, precise, accurate, and robust chiral HPLC method for the determination of R -Lif in S -Lif. The amount of enantiomeric impurity R -Lif in S -Lif increased under all stress and photostability test conditions without exceeding the acceptable impurity limit, with the most significant increase observed at elevated temperatures (105 °C) for both the drug substance in powder form and the ophthalmic drug solution. [Display omitted] • The first enantiomeric impurity LC method developed and validated for lifitegrast. • Specificity was demonstrated using Lif. Imp. A-D and stressed lifitegrast samples. • Racemization of lifitegrast was studied under stress and stability conditions. • The chiral HPLC method was applied to the analysis of the ophthalmic drug. [ABSTRACT FROM AUTHOR]