A new sensitive flow‐injection chemiluminescence method for the determination of H₂‐receptor antagonists

Abstract

Abstract Based on the chemiluminescence (CL) intensity generated from the potassium ferricyanide [K 3 Fe(CN) 6 ]–rhodamine 6G system in sodium hydroxide (NaOH) medium, a new sensitive flow‐injection chemiluminescence (FI–CL) method has been developed, validated and applied for the determination of three kinds of H 2 ‐receptor antagonists: cimetidine (CIMT), ranitidine (RANT) hydrochloride and famotidine (FAMT). Under the optimum conditions, the linear range for the determination was 1.0 × 10 −9 –7.0 × 10 −5 g/ml for CIMT, 1.0 × 10 −9 –5.0 × 10 −5 g/mL for RANT hydrochloride and 5.0 × 10 −9 –7.0 × 10 −5 g/mL for FAMT. During 11 repeated measurements of 1.0 × 10 −6 g/mL sample solutions, the relative standard deviations (RSDs) were all <5%. The detection limit was 8.56 × 10 −10 g/mL for CIMT, 8.69 × 10 −10 g/mL for RANT hydrochloride and 2.35 × 10 −9 g/mL for FAMT (S:N = 3). This method has been successfully implemented for the analysis of H 2 ‐receptor antagonists in pharmaceuticals. Copyright © 2007 John Wiley & Sons, Ltd.