A validated stability indicating LC-MS compatible RP-HPLC assay and dissolution methods for marketed formulation Stribild

Objective: The prime objective of the current work is to develop a simple, rapid, efficient, economical and stability indicating LC-MS (liquid chromatography–mass spectroscopy) compatible RP - HPLC (reverse phase – high performance liquid chromatography) method for the analysis of emtricitabine (EMT), tenofovir disoproxil fumarate (TDF), cobicistat (COB) and elvitegravir (ELV) in bulk, marketed formulation (Stribild) and in In-vitro dissolution method. Method: The chromatography was achieved on Unisol C18 column (250 × 4.0 mm, 3 µ) with a mobile phase combination of acetate buffer (adjusted with dilute glacial acetic acid to pH 4) and acetonitrile in gradient mode at a flow rate of 1mL/min and the detection was performed at 260 nm using PDA (photo diode array) detector. Forced degradation studies were performed and the % degradation under various stress conditions was calculated. The developed RP-HPLC method was applied for Stribild tablets to study the dissolution profile. Results: The retention times for emtricitabine, tenofovir disoproxil fumarate, cobicistat and elvitegravir were 5.7, 12.1, 16.3 and 19.4 min respectively. The % degradation was below 20% which is within the limits. The percent drug release was found to meet USP specification, i.e. not less than 80% of amount of labeled drug EMT, TDF, COB and ELV dissolved in 30min. Conclusion: The method was validated as per ICH guidelines and all the validation parameters were within the compendial requirements. The proposed method can be successfully adopted for the analysis of Stribild tablets in pharmaceutical industries. Keywords: Stribild, emtricitabine, tenofovir disoproxil fumarate, cobicistat, elvitegravi

DEVELOPMENT AND VALIDATION OF UV SPECTROPHOTOMETRIC AND REVERSED PHASE‑HIGH PERFORMANCE LIQUID CHROMATOGRAPHY ‑ PDA METHODS FOR THE ESTIMATION OF ALOGLIPTIN BENZOATE

Objective: To develop and validate simple, rapid, precise, accurate, and economical UV spectrophotometric and reverse phase high performanceliquid chromatographic methods for the estimation of alogliptin benzoate (AGP).Methods: UV spectrophotometric method was performed using UV/Vis double beam spectrophotometer with a spectral bandwidth of 1 nm and1.0 cm matched quartz cells. The maximum absorbance of AGP was observed at 276 nm using methanol as solvent. Reversed phase-high performanceliquid chromatography (RP-HPLC) method was carried out on a Unisol reverse phase C18 column (150 mm × 4.6 mm, 3 μm) with a mobile phasecomposed of methanol and 10 mM ammonium acetate buffer (adjusted to pH 5.0 with glacial acetic acid) in the ratio of 80:20 v/v with a flow rate of0.8 ml/minutes.Results: The linearity of methods was found to be in the range of 5-35 µg/ml (UV) and 20-100 µg/ml (RP-HPLC) and the correlation coefficient was0.999 for both the methods. The regression equations were y = 0.028x + 0.023 (UV) and y = 28,58,942x - 4,33,647 (HPLC). The retention time of AGPwas 2.37 minutes.Conclusion: The proposed methods were validated in terms of linearity, precision, accuracy, specificity, robustness, limit of detection, and limit ofquantitation as per International Conference on Harmonization Q2 R1 guidelines. Thus, the proposed methods are novel, sensitive, and reliable andcan be successfully used for the quantitation of AGP.Keywords: Alogliptin benzoate, UV-visible spectrophotometer, Reversed phase-high performance liquid chromatography, International Conferenceon Harmonization guidelines

DEVELOPMENT AND VALIDATION OF STABILITY INDICATING REVERSE PHASE HIGH‑PERFORMANCE LIQUID CHROMATOGRAPHIC METHOD FOR THE ESTIMATION OF PIRIBEDIL IN BULK DRUG

ABSTRACTObjective: A simple, precise, fast, economic, accurate, robust, and stability indicating isocratic reverse phase high-performance liquid chromatographicmethod was developed for the analysis of Piribedil.Method: The chromatographic conditions were standardized using Unisol C-18 (4.6 × 150 mm × 3.0 μ) column with UV detection at 244 nm, and themobile phase composed of methanol:acetate buffer-pH 5.0 (85:15, v/v).Results: The retention time of Piribedil was found to be 3.4 minutes. The calibration curve was linear with correlation coefficient of 0.999 over aconcentration range of 20-100 μg/ml with linear regression equationy=74,69,224.37x−39,46,924.90. The limit of detection and limit of quantitationwere found to be 0.04 and 0.4 μg/ml, respectively.Conclusion: The proposed method has been validated according to the ICH guidelines. Piribedil was subjected to stress conditions includingacidic, alkaline, oxidation, photolysis, and thermal degradation. Piribedil is more sensitive to photolytic stress. There are no interfering peaks fromdegradation products at analyte retention time, and thus the method is specific for the estimation of Piribedil in the presence of degradation products.Thus, the proposed method can be successfully applied in the routine quality control and stability samples of Piribedil in bulk drug.Keywords: Piribedil, Validation, Stability indicating, Reverse phase high-performance liquid chromatographic

DEVELOPMENT AND VALIDATION OF STABILITY INDICATING SIMULTANEOUS UVSPECTROPHOTOMETRIC METHOD FOR DETERMINATION OF EMTRICITABINE, TENOFOVIR DISOPROXIL FUMARATE, COBICISTAT, AND ELVITEGRAVIR IN PURE AND PHARMACEUTICAL DOSAGE FORM

 Objective: The objective of this research work was to develop and validate a simple, precise, and accurate new ultraviolet-spectrophotometric method for the simultaneous estimation of emtricitabine (EMT), tenofovir disoproxil fumarate (TDF), cobicistat (COB), and elvitegravir (ELV) in pure and pharmaceutical marketed dosage form (stribild).Methods: Simultaneous equation method (Vierordt's method) was developed for simultaneous determination of several mixtures containing two or more absorbing drugs (p, q, r, and s) each of which absorbs at the λ max of the other. Forced degradation studies were also conducted, and the drugs were subjected to various stress conditions such as acid hydrolysis, base hydrolysis, oxidative, photolytic, and thermal degradation.Results: The λ max of EMT, ten TDF, COB, and ELV are 283 nm, 259 nm, 240 nm, and 258 nm, respectively. The linearity ranges for the four drugs are EMT (4–24 μg/ml), TDF (10–50 μg/ml), COB (10–120 μg/ml), and ELV (2–10 μg/ml).Conclusion: The Vierordt's method was successfully applied for simultaneous determination of EMT, TDF, COB, and ELV in a mixture of sample solution (pharmaceutical dosage form) and the results obtained were validated and found to be accurate, precise, linear, rugged, and robust