Chemiluminescence flow injection analysis of amoxycillin by a permanganate-based reaction

A new application of chemiluminescence for the determination of amoxycillin in flow injection mode is presented. The method is based upon the direct chemiluminescence reaction of amoxycillin with KMnO₄ in acidic medium in presence of quinine sulfate. The chemiluminescence intensity was linearly related to the concentration of amoxycillin within 0.05-10 μg mL^-1 range with a detection limit (3σ) of 0.02 μg mL^-1 and a sample measurement frequency of 90 samples h-¹. The relative standard deviation is 2.3% for 1.0 μg mL^-1 amoxycillin solution in 11 repeated measurements. The method was successfully applied to the analysis of amoxycillin in capsules.