Determination of Related Substances in Lansoprazole Intermediate by Using Stability-indicating HPLC Method

The present study determines the related substances in lansoprazole intermediate by using stability-indicating HPLC method. Lansoprazole intermediate is the critical raw material for synthesizing the drug substance, lansoprazole. The purity of the lansoprazole intermediate determines the quality of the lansoprazole drug substance with high yield in the synthetic process during the manufacturing. A novel, reversed-phase liquid chromatographic method was developed and validated to determine related substances in the lansoprazole intermediate. The symmetric peak shape was on a C18 stationary phase with the dimensions of 250 mm column length, 4.6 mm as internal diameter, and 5 microns particles with an economical and straightforward mass-compatible mobile phase combination of formic acid/triethylamine and acetonitrile delivered in gradient mode at a flow rate of 1.0 mL/min at 260 nm. The resolution between the lansoprazole intermediate and its impurities in the developed method was more than 2.0, indicating a significant separation. Regression analysis shows a correlation coefficient greater than 0.999 for lansoprazole intermediate and related substances. Lansoprazole Intermediate's detection and quantitation limits and impurities are 0.01% and 0.005%, respectively. This method indicates that the recovery at different levels is 90 to 110% accurate. The test solution was stable in the diluent for 48 hours. The results of forced degradation studies implied that the Lansoprazole Intermediate was sensitive to acid/base hydrolysis and oxidation conditions, and the mass balance was close to 99.5%. This study used the HPLC system Agilent Technologies 1200, a quaternary pump, an autosampler, and a diode array detector. The chromatographic output signal was monitored and processed by Empower software on an Intel Core i5 computer (Dell).