RESUMO
Objectives: Design of experiments assisted spectrophotometric methods have been established for the quantification of saxagliptin in pharmaceutical formulation via charge transfer complexation and Schiff's base formation. Materials and Methods: Box-Behnken design was exploited in method-1, involved the measurement of absorbance of green/blue-colored complex (at 600 nm), formed by the reaction of saxagliptin with 3-methyl-2-benzothiazolinone hydrazone in the presence of ferric chloride. The central composite design was employed in method-2, involved the determination of absorbance of Ruhemann's purple (at 585 nm), formed by the reaction of the primary amine group of saxagliptin with ninhydrin reagent in presence of sodium hydroxide. Optimization of reaction variables namely, reagent concentration (A), oxidizing agent/alkalinity (B) and reaction/heat time (C) was performed through response surface methodology for the response (Y) i.e. absorbance of colored compound. The reliability of both methods was investigated through validation as per International Council for Harmonisation guidelines. Results: Saxagliptin executed linearity in the concentration range of 0.01-0.25 µg/mL and 1-10 µg/mL by method-1 and 2. A high value of molar absorptivity, low values of Sandell's sensitivity and limit of detection/limit of quantification divulges the good sensitivity methods. The % assay of saxagliptin in the marketed formulation was found to be 100.27 and 99.86 by method-1 and method-2, respectively. Conclusion: The proposed eco-friendly and economical methods can be routinely employed in quality control for the analysis of saxagliptin in the pharmaceutical dosage forms.
RESUMO
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.
