New stability chiral RP-HPLC method for degradation products determination in midodrine hydrochloride

Enantiomeric resolution of the drug and complete separation from its degradation products was successfully achieved on a PAK IG-3 (150 × 4.6 mm i.d., 3 µm particle size) column, using UV detector at a wavelength of 290 nm, with mobile phase consisting of acetonitrile, 20 mM ammonium bicarbonate at the ratio of 95:05 (v/v), and a flow rate of 0.7 mL/min. In order to subjected to stress conditions, the drug has been exposed to alkaline, acidic, neutral, oxidative, and photolytic conditions. The products of degradation were well resolved from the main peak and proved the method's stability-indicating method. The method linear ranged between 10-110 μg/mL and 5-100 μg/mL for (+) and (-) midodrine enantiomers and regression analysis showed a correlation coefficient value (r²) of 0.999. The recovery of the method was found to be in the range of 99.1-101.2%. The detection limit for the (+) and (-) enantiomers was found to be 4 μg/mL and 1 μg/mL, respectively. The HPLC method was validated as per ICH guidelines with respect to specificity, precision, linearity, and robustness.