Validation of HPLC and FIA Spectrophotometric Methods for the Determination of Lansoprazole in Pharmaceutical Dosage Forms and Human Plasma

A chromatographic and aspectrophotometric methods for the quantitative determination of lansoprazole in pharmaceutical combinations and human plasma were developed. The analytical parameters were studied according to International Conference on Harmonization guidelines. The Flow Injection Analysis (FIA) method is based on the oxidation of lansoprazole by a known excess of N-bromosuccinimide (NBS) in an acidic medium, followed by a reaction of excess oxidant with chloranilic acid (CAA) to bleach its purple color. The separation was carried out using RP-C18 column with a mobile phase composed of ACN: TEA: phosphate buffer (60: 0.2: 39.8 v/v) adjusted to pH = 4.