IDENTIFICATION AND QUANTIFICATION OF POTENTIAL IMPURITIES USING LC-PDA COUPLED WITH NEW QDa MASS DETECTOR IN A NEW SINGLE TABLET REGIMEN CONTAINING DOLUTEGRAVIR, EMTRICITABINE AND TENOFOVIR DISOPROXIL FUMARATE TABLETS USED IN HIV-1 PREVENTION

Abstract

The objective of this current work was to develop and validate a rapid, sensitive, rugged, simple, single method for the determination and quantification 
of degradation products as well as process impurities by HPLC coupled with PDA, QDA mass detector and same method was also scalable to UPLC 
for a fixed dose combination containing dolutegravir, emtricitabine and tenofovir disoproxil fumarate. Chromatographic separation was achieved using 
a new Core-Shell Bi-phenyl column for both HPLC and UPLC and a gradient programme consisting of Mobile phase A: Ammonium acetate (pH 3.0 
buffer) and Mobile phase B: Ammonium Acetate (pH 3.0 buffer) with Methanol and Acetonitrile. The run time was 120 minutes for HPLC and 45 
minutes for UPLC within which dolutegravir, emtricitabine, tenofovir disoproxil fumarate and its fourteen related compounds were eluted. Drug was 
subjected to hydrolysis (acid and base), oxidative, photolytic and thermal stress conditions. The unknown degradation products were identified by 
PDA/QDA mass detector. Which revealed protonated molecular ion peaks [M=H at m/z DP1-418.21 and DP2-418.18   for sample preparation in acid 
and base hydrolysis,  at m/z DP3-416.04, DP4-663.17, DP5-490.14, DP6-819.21 and DP7-606.14 for  thermal degradation sample and at m/z DP8
438.18 and DP9-438.18 for Dolutegravir  API in acid hydrolysis condition. A cogent mechanism for the formation of degradation and process impurities 
was proposed. The performance of the developed method was validated as per International Conference on Harmonization guidelines (ICH) with respect 
to specificity, linearity, limit of detection (LOD), limit of quantification (LOQ), accuracy, precision and robustness.