Flow-injection chemiluminescence determination of lisinopril using luminol-KMnO₄ reaction catalyzed by silver nanoparticles

A simple, sensitive, and rapid chemiluminescence method combined with flow-injection analysis was developed for the determination of lisinopril. It was found that the chemiluminescence (CL) signal arising from the reaction of alkaline luminol with KMnO₄ could be significantly increased by addition of lisinopril in the presence of silver nanoparticles. The experimental parameters affecting the chemiluminescence reaction were carefully studied and the chemiluminescence reaction mechanism was briefly discussed. Under the selected conditions, the chemiluminescence intensity was proportional to the concentration of lisinopril ranging from 0.1 mg/L to 20.0 mg/L. The detection limit was 0.027 mg/L lisinopril and the relative standard deviation for 4.0 mg/L lisinopril solution was 1.9% over eleven repeated measurements. The proposed method was applied to the determination of lisinopril in tablets and spiked human urine samples.