Development and Validation of a Rapid and Sensitive LC-APCI-MS/MS Method for the determination of three N-nitrosamine impurities in Varenicline tartrate drug substance and drug products

Abstract

Nitrosamines impurities may be present in low levels in a variety of products that people are exposed to every day. After thorough investigations, regulatory agencies have outlined that the formation of nitrosamines is possible in the presence of secondary, tertiary, or quaternary amines and nitrite salts under acidic reaction conditions. For safety purpose, all API manufacturers must be developed methods to monitor the low levels of each nitrosamine impurity before the release the individual batches. In this article, we have developed novel, rapid and sensitive liquid chromatography Atmospiric pressure chemical ionization Mass spectroscopy (LC-APCI-MS/MS) method for the determination of N-Nitroso Dimethylamine (NDMA), N-Nitroso Diethylamine (NDEA) and N-Nitroso varenicline impurities in the Varenicline Tartrate drug substance and Drug products. Chromatographic separation is achieved using Inert sustain AQ C18 150 × 4.6mm, 3.0μ column with 0.1% formic acid in water as mobile phase A and 0.1% formic acid in methanol as mobile phase B at the 0.6 mL/min flow rate by using gradient mode of elution upto the 25 minutes total run time. The three impurities are successfully ionized and quantified in positive mode of atmospheric pressure chemical ionization (APCI) using multiple reaction monitoring (MRM). This method was validated according to ICH Q2 (R1) guidelines. The method provided excellent S/N ratios with a high linearity range of 0.66-19.88 ppm with respect to Varenicline Tartrate sample concentrations with a regression coefficient >0.995. The recovery for the method was established with a protocol of three-step sample preparation and was satisfactory within 85-115%. The determined LOQ (0.66 ppm) and LOD (0.22 ppm) values are very low with respect to sample concentration which shows the sensitivity Performance of the method. The method can be routinely applied for the detection of N-nitrosamine impurities (NDMA, NDEA and N-Nitroso varenicline) in Varenicline Tartrate drug substance and Drug products.