Development & validation of stability indicating HPLC method for determination of Solifenacin in bulk formulations

A stability indicating, isocratic, rapid, specific, and sensitive high performance liquid chromatographic (HPLC) method was developed and validated for determination of Solifenacin in bulk drug. The quantitative determination of SOLIFENACIN was performed on a Hypersil C₈ (250mm × 4.6 mm i.d., 5 μm) column with mobile phase consist of 10 mM potassium dihydrogen phosphate buffer with 0.1% v/v TEA in Milli-Q water (pH-3): Acetonitrile (60:40 %v/v) pumped at a flow rate of 1 mL min^-1 at 25°C. The eluents were monitored at wavelength 210 nm using photo diode array (PDA) detector. The drug was subjected oxidation, hydrolysis and heat to apply stress conditions. The developed method was validated as per ICH guideline for the parameters such as specificity, linearity, precision, accuracy, limit of detection, limit of quantification and found to be satisfactorily. The drug was found to be hydrolyzed in acidic and alkaline conditions. We also found the degradation under oxidative stress condition. The developed method was able to separate all degradation product generated under forced degradation studies and drug peak was eluted at 7.82 min. The response was linear in the drug concentration range of 1-30 μg mL^-1 (r²=0.9991) with limit of detection and limit of quantification 0.019 μg mL^-1 and 0.063 μg mL^-1 respectively. The Relative Standard Deviation (RSD) values for intra- and inter-day precision studies were 0.50% and 0.62% respectively. Mean % recovery (mean ± SD) was found to be 100.51 ± 1.98.