Development and Validation of a Stability-Indicating RP-HPLC Method by a Statistical Optimization Process for the Quantification of Asenapine Maleate in Lipidic Nanoformulations

A stability-indicating RP-HPLC method was developed for quantification of asenapine maleate (ASPM) in lipid nanoformulations. The proposed method was used to assess intrinsic stability of ASPM by conducting force degradation study. The results indicated no considerable degradation of ASPM on subjecting it to hydrolytic, oxidative, thermal and photolytic stresses. The method was validated according to ICH Q2(R1) guidelines by employing Full factorial design using Design-Expert® software. ASPM was precisely and accurately quantified in nanoparticles by separating it on Hyperclone BDS C₁₈ using 80-20% v/v mixture of potassium phosphate solution containing 0.1% v/v triethylamine and acetonitrile. The effect of flow rate, pH, acetonitrile content and column temperature was assessed on method responses. The current method was linear in the range of 0.1-20 μg/mL with limit of detection (LOD) and limit of quantification (LOQ) of 29 and 89 ng/mL, respectively. The method was precise and accurate in the determination of ASPM with peak area RSD and recovery of <1.0% and 97-101% in bulk drug solution and of <1.0% and 92-104% in nanoformulations, respectively. Analysis of variance indicated the significance (P < 0.0001) of a statistical model in validating the method with respect to change in independent chromatographic factors. The developed method was successfully employed in determining ASPM content in bulk and lipid nanoformulations.