A Novel, Validated Stability-Indicating UPLC Method for the Estimation of Lansoprazole and its Impurities in Bulk Drug and Pharmaceutical Dosage Forms

A novel, reversed-phase ultra-performance liquid chromatographic method was developed and validated for the determination of the assay and related substances of Lansoprazole (LAN) in bulk drug and capsule dosage forms. The related substances include degradation and process-related impurities. The method was developed using the Waters Acquity BEH C18 column and gradient program with mobile phase A as a pH 7.0 phosphate buffer and methanol in the ratio of 90: 10 (v/v), and mobile phase B as methanol and acetonitrile in the ratio of 50:50 (v/v). Lansoprazole and its impurities were monitored at 285 nm. Lansoprazole was subjected to the stress conditions of oxidative, acid, base, hydrolytic, thermal, humidity, and photolytic degradation and found to degrade significantly under acid and oxidative stress conditions. The degradation products were well-resolved from the main peak and its impurities, proving the stability-indicating power of the method. The performance of the method was validated according to the present ICH guidelines for specificity, limit of detection, limit of quantification, linearity, accuracy, precision, ruggedness, and robustness.