Rapid Reversed Phase High Performance Liquid Chromatographic Assay Method for Ranitidine Hydrochloride in Dosage Forms

Abstract

A HPLC method with photometric detection has been developed for the rapid assay of ranitidine hydrochloride in dosage forms and samples from tablet dissolution testing. This method also separates ranitidine from its related compound ranitidine S-oxide. Analyses were carried out on a Microsorb-MV C18 column, with a (1:1) mixture of methanol-0.01 M Na₂HPO₄ (pH 7.0) as the mobile phase, and detection at 320 nm. At a flow rate of 1.0 mL/min, typical retention times for ranitidine and its S-oxide compound were 3.50 min and 1.95 min, respectively. Detector responses were linearly related to on column concentrations of ranitidine and ranitidine S-oxide in the ranges 0.035–9.000 μq and 0.005–0.320 μg, respectively. Recoveries of ranitidine from spiked synthetic formulations simulating tablets, injections and syrups ranged from 99.7 ± 0.5% to 100.5 ± 0.5% of the added amount (n = 2). For assay purposes, tablets were extracted into or liquid samples (injections, syrups) were quantitatively diluted with methanol-water (1:1), and the solutions were injected onto the column. Samples from tablet dissolution tests required no preliminary preparation. Assay values by the proposed method were found to agree closely with those obtained using methods in the USP XXII.