A New Validated Stability Indicating Ion-Pair HPLC Method for Evaluation of Impurities of Pramipexole from Low Dose Extended Release Formulation

Abstract

A new validated stability indicating ion-pair HPLC method was developed for evaluation of impurities of pramipexole from low dose extended release tablet formulation. Challenges related to extraction and recovery of impurities along with active ingredient-pramipexole from inactive ingredient matrix which contain HPMC-polymer, high placebo to drug ratio (100:1), were fully addressed. Tablets were subjected for forced degradation studies and oxidative impurities (N- and S-oxides) were identified by LC-MS. All impuritiies as well as placebo peaks were well resolved from pramepexole peak. The method was developed by using Inertsil ODS-3V column with a pre-guard column. Sodium salt of octane sulphonic acid as ion pair was used along with phosphate buffer (pH 2.7) with flow rate of 1 mL/min, linear gradient using acetonitrile as organic modifier. Pramipexole and its related impurities were monitored at UV wavelength of at 264 nm. The finalized method consists was fully validated as per ICH Q2 (R1) guideline.