Validation of a liquid chromatographic method for the determination of ranitidine hydrochloride residues on surfaces in the manufacture of pharmaceuticals

A liquid chromatographic method for determination of the residues of ranitidine hydrochloride on various surfaces employed in drug manufacture is described. Cotton swabs, moistened with a methanol–water (1:1, v/v) mixture were used to remove any residues of drugs from glass, vinyl, and stainless steel surfaces, and gave recoveries of 85%, 78% and 90%, respectively. Residues were determined by high-performance liquid chromatography on a C18 column at 25°C with methanol–ammonium acetate (40:60 v/v) pH 6.7 as the mobile phase and detection at 320 nm. The method was validated over a concentration range of 20–10 000 ng/ml and had a detection limit of 2 ng/ml.