NOVAL METHOD DEVELOPMENT AND VALIDATION FOR THE DETERMINATION OF THREE POTENTIAL GENOTOXIC IMPURITIES IN DARUNAVIR PROPYLENE GLYCOLATE DRUG SUBSTANCE BY LC-MS/MS TECHNIQUE

A Liquid Chromatography-Mass Spectrometry (LC-MS/MS) method was used for quantification of potential genotoxic impurities (PGI) in the Darunavir propylene glycolate drug substance (API). Chromatographic separation was achieved using a column UPLC BEH C18, 1.7 μm (100×2.1mm), with a Mobile-phase-A was ammonium bi carbonate and Mobile-phase-B was acetonitrile in gradient elution mode at a flow rate of 0.3 ml/min and injection volume is 2.0 µL. Quantification of impurities was carried out using triple quadrupole mass detection with electrospray ionization in multiple reaction monitoring mode. The method was fully validated with good linearity over the concentration range of 0.23 to 1.69 μg/g of the Darunavir propylene glycolate test concentration for all Genotoxic impurities. The correlation coefficient obtained in each case was 0.999. The recoveries were found satisfactory over the range between 98.1 to 101.4% for all selected impurities. A novel selective, highly sensitive and hyphenated analytical method using LC-MS/MS coupled with negative electrospray ionization has been developed for quantification of genotoxic impurities like Nitro benzene sulfonic acid and Methyl-4-amino benzene sulfonate at in Darunavir propylene glycolate API.