Chromatographic study of sitagliptin and ertugliflozin under quality-by-design paradigm

Abstract The present study entails the systematic development and validation of a stability-indicating RP-HPLC method for the analysis of sitagliptin and ertugliflozin in a fixed-dose combination. Analytical quality by design (AQbD) concepts were used to define critical method variables, employing Pareto risk assessment and a Placket-Burman screening design, preceded by a Box-Behnken design with response surface analysis to optimise critical method parameters such as % acetonitrile (X1), buffer pH (X2) and column oven temperature (X3). Multiple response optimisation (Derringer's desirability) of variables was accomplished by studying critical analytical attributes, such as resolution, retention time and theoretical plates. The title analytes were separated effectively on a PRONTOSIL C18 column at 37 °C using a mobile phase of acetonitrile:acetate buffer, pH 4.4 (36:64 percent v/v), pumped at a flow rate of 1 mL/min, and UV detection at 225 nm. Linearity was observed over a concentration range of 25-150 µg/mL and 3.75-22.5 µg/mL at retention times of 2.82 and 3.92 min for sitagliptin and ertugliflozin, respectively. The method obeyed all validation parameters of the ICH Q2(R1) guidelines. The proposed robust method allows the study of the selected drugs in pharmaceutical dosage forms as well as in drug stability studies under various stress conditions.

Quality-by-Design Approach for Chromatographic Analysis of Metformin, Empagliflozin and Linagliptin.

New analytical quality by design-oriented HPLC method with multiple response optimization (Derringer's desirability function) was demonstrated for simultaneous analysis of three antidiabetic drugs (metformin hydrochloride/empagliflozin/linagliptin) in a fixed-dose combination. Central composite design was employed for systematic optimization of critical method parameters, namely, % organic phase (X1), aqueous phase pH (X2) and flow rate (X3) while resolution, capacity factor and theoretical plate number as critical analytical attributes. Effective chromatographic separation of title analytes was accomplished on Std. Discovery C18 column at 30°C with mobile phase comprising acetonitrile: phosphate buffer pH 5 (38:62% v/v), pumped at a flow rate of 1 mL/min by isocratic elution pattern and UV detection at 222 nm. The model is rectilinear in the range of 1.0-200, 0.2-40 and 0.1-20 µg/mL at retention times of 3.04, 3.93 and 5.99 min for metformin, empagliflozin and linagliptin, respectively. The method obeyed all validation parameters of ICH Q2(R1) guidelines. The proposed HPLC method was highly robust for method transfer, regulatory flexibility within design space and can be used for assay of pharmaceutical dosage forms comprising these analytes. The proposed method was applied for stability studies of drugs under various stress conditions.

Spectrophotometric Quantification of Anti-inflammatory Drugs by Application of Chromogenic Reagents.

OBJECTIVES: Simple, specific, accurate, precise, sensitive, and cost effective spectrophotometric methods were developed and validated for quantification of the drugs lornoxicam (LOR) and mesalamine (MES) in pure form and in pharmaceutical formulations. MATERIALS AND METHODS: A Shimadzu UV-1800 double-beam UV-Visible spectrophotometer having a spectral bandwidth of 0.1 nm with wavelength accuracy ±0.1 nm with a pair of 1 cm path length matched quartz cells was used to measure the absorbance of the resulting solution. Method I was used for the quantification of LOR, based on measurement of the absorbance of bluish green chromogen complex at 760 nm, which is formed by the reaction of LOR with ferric chloride and potassium ferricyanide (redox technique). Method II was used for the quantification of MES, based on measurement of the absorbance of yellow chromogen at 400 nm, which is formed by the condensation reaction of the primary amino group of MES with salicylaldehyde reagent (SA) (Schiff base formation). RESULTS: Both methods obeyed Beer's law in the concentration range of 0.5-4.5 µg/mL and 0.2-1.7 µg/mL with good correlation coefficients of 0.9974 and 0.998 for methods I and II, respectively. CONCLUSION: The developed method is simple, sensitive, and specific, which was validated statistically as per ICH guidelines, and can be used in the routine analysis of LOR and MES in pharmaceutical dosage forms.

Development of dissolution test method for a telmisartan/amlodipine besylate combination using synchronous derivative spectrofluorimetry

The dissolution process is considered an important in vitro tool to evaluate product quality and drug release behavior. Single dissolution methods for the analysis of combined dosage forms are preferred to simplify quality control testing. The objective of the present work was to develop and validate a single dissolution test for a telmisartan (TEL) and amlodipine besylate (AML) combined tablet dosage form. The sink conditions, stability and specificity of both drugs in different dissolution media were tested to choose a discriminatory dissolution method, which uses an USP type-II apparatus with a paddle rotating at 75 rpm, with 900 mL of simulated gastric fluid (SGF without enzymes) as the dissolution medium. This dissolution methodology provided good dissolution profiles for both TEL and AML and was able to discriminate changes in the composition and manufacturing process. To quantify both drugs simultaneously, a synchronous first derivative spectrofluorimetric method was developed and validated. Drug release was analyzed by a fluorimetric method at 458 nm and 675 nm for AML and TEL, respectively. The dissolution method was validated as per ICH guidance.

O processo de dissolução é considerado como uma importante ferramenta in vitro para avaliar a qualidade do produto e o comportamento de liberação do fármaco. Prefere-se um ensaio único de dissolução para formas farmacêuticas contendo associação de fármacos pela simplificação dos testes de controle de qualidade. O objetivo do presente trabalho foi desenvolver e validar um teste de dissolução único para forma farmacêutica comprimidos contendo telmisartana (TEL) e besilato de anlodipino (AML) associados. Condições "sink", estabilidade e especificidade de ambos os fármacos nos diferentes meios de dissolução foram avaliadas para selecionar um método de dissolução discriminatório, que utiliza um aparato do tipo II da USP, com pás girando a 75 rpm e 900 mL de fluido gástrico simulado (SGF sem enzima) como o meio de dissolução. Estas condições proporcionaram bons perfis de dissolução para ambos, TEL e AML, sendo capaz de discriminar as mudanças na composição e processo de fabricação. Para quantificar os dois fármacos simultaneamente, um método de fluorescência derivada sincronizado foi desenvolvido e validado. A quantidade de fármaco liberado foi analisada pelo método fluorimétrico em 458 e 675 nm para a AML e TEL, respectivamente. O método de dissolução foi validado de acordo com a orientação da ICH.