ISOLATION AND CHARACTERISATION OF NOVEL IMPURITY OF LANSOPRAZOLE FORMED IN THERMAL STRESS CONDITION

Objective: The aim of the research work is to study the degradation of Lansoprazole in stress condition which is a proton pump inhibitor and controls the production of gastric acid in stomach. Thermal stress condition has been used to check the stability of the compound, in which one new degradation product was generated.Methods: The USP method for the identification of related compounds of Lansoprazole shows three known impurities N-Oxide impurity, Sulphone impurity and sulphide impurity. New degradation product formed in stress condition has been separated from the drug product and other known impurities by using Clarity Oligo RP column (250 mm x 4.6 mm, 5µ) and 10 mM Ammonium Acetate -Acetonitrile as a mobile phase. Same method has been scaled up on mass based preparative HPLC for the isolation of new degradation product.Results: The isolated impurity was structurally elucidated with 1H NMR, [13]C NMR, HMBC, HSQC and HRMS. From the characterization studies it was found that novel impurity has 164.04 molecular weight with molecular formula C8H8N2S. The degradation product's structure was matched with 2-(Methylthio)-1H-benzo[d]imidazole per recorded analysis data.Conclusion: Isolated impurity was found to be novel and not reported in the literature. This method can be used for the degradation study of Lansoprazole and purification of novel impurity from drug and other degradation product