No abstract

A stability-indicating ultraperformance liquid chromatographic method has been developed for the quantitative determination of degradation products and process-related impurities of daclatasvir in a pharmaceutical dosage form. Chromatographic separation was achieved on a polar Waters ACQUITY BEH phenyl 100 × 2.1 mm, 1.7-μm column using the gradient program consisting of mobile phase A: 0.03 M sodium perchlorate with 0.002 M of 1-octanesulfonic acid sodium salt (pH 2.5 buffer) and mobile phase B: 0.03 M sodium perchlorate with 0.02 M of 1-octanesulfonic acid sodium salt (pH 2.5 buffer) with acetonitrile in the ratio of 20:80% v/v. A flow rate of 0.4 mL/min is maintained under ultraviolet detection at 305 nm. The run time was 15 min, within which daclatasvir, its related impurities and unknown degradants were well resolved. The method was found to produce symmetric and sharp peaks with good separation between process-related impurities and degradation impurities. Samples were subjected to hydrolysis (acid and base), oxidative, photolytic and thermal stress conditions to prove the stability-indicating nature of the method. The unknown degradation products were identified by PDA/QDa mass detector. This mass spectrum reveals protonated molecular ion peaks [M + H]+ at m/z DP1-582.4 in acid and base hydrolyses and m/z DP2-778.5 in peroxide hydrolysis. The method was validated in terms of specificity, precision, linearity, accuracy, limit of detection, limit of quantification and robustness as per ICH guidelines.

Developing a single method for the quantification of related compounds for a combination product containing three active ingredients is difficult task. Separation and compromising run time to elute all known and unknown degradation products are crucial for a combination product. The aim of current work is to develop a new stability indicative method and validate for a fixed dose combination product containing dolutegravir, lamivudine, tenofovir disoproxil fumarate and their potential impurities in a single run by HPLC. The critical separation between dolutegravir, lamivudine, tenofovir disoproxil fumarate and its impurities was successfully attained by a new core-shell bi-phenyl, 250x4.6mm, 5µm column with a run time of 150 min. The run time was 150min. Forced degradation studies were verified to prove the stability-indicating nature of the method. Stability-indicating nature was confirmed by peak purity of all the three active components and impurities. The developed method was validated to prove the potentiality of the method as per ICH guidelines with respect to specificity, linearity, accuracy, precision ad robustness. The sensitivity of the method was proved by establishing limit of detection (LOD) and limit of quantification (LOQ) of for dolutegravir, lamivudine, tenofovir disoproxil fumarate and potential impurities.

A new UPLC method was developed for identification and quantification of process related impurities and degradation products in a new fixed dose combination product of empagliflozin and linagliptin tablets, which is used to treat type-2 diabetes. Chromatographic separation was obtained using a new phenomenex Luna omega polar C18, 100x2.1mm, 1.6µ and a gradient programme consisting of Mobile phase A: 10mM Potassium dihydrogen orthophosphate pH-3.0 and Mobile phase B: acetonitrile and methanol (55:45%v/v). Degradation impurities were monitored at a common wavelength of 225nm. The run time was 40 minutes within this run time the five related compounds, all major degradation impurities of empagliflozin and linagliptin were eluted which reduces the analysis time and solvent consumption. The combined drugs as well as individual blends were subjected to hydrolysis (water, acid and base), oxidative, photolytic and thermal stress conditions. Mass of major unknown degradation products were determined by LC-PDA coupled with a new QDA mass detector. The protanated molecular ion peaks for linagliptin at M+H were DP1-514.19 in water, acid, base, oxidative, photolytic and thermal stress conditions. DP2-515.14 in acid and base hydrolysis. DP3-544.18 in acid hydrolysis. For empagliflozin DP4-365.13 in base hydrolysis. DP5-487.16 and DP6-487.14 in peroxide hydrolysis. DP7-470.91, DP8-502.08, DP9-538.01, DP10-326.98 and DP11-293.02 in acid hydrolysis. 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.

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 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.