A New Designed Cell For Luminol Based Electrochemiluminescence By Bi-potentiostatic Excitation For Flow-injection Analysis

A new designed luminol-based electrochemiluminescent(ECL) cell by bi-potentiostatic excitation was developed for the utilization as a coupled-detector of a ?ow injection analysis system(Bi-ECL–FIA). In this ?ow cell, four electrodes were ?xed in, here a piece of indium tin oxide coated glass was applied as one of the working electrodes while another Pt net served as second one. Two electrolysis voltages from a dual-potentiostat powered two working electrodes. Thus, continuous and constant ECL signal could be obtained. After optimizing the experimental conditions, it was showed that the Bi-ECL–FIA system provided higher sensitivity than conventional pulsed mode. The response of hydrogen peroxide or resveratrol on this system was investigated, indicating a 7.4 ×10-11mol/L of detection limit for H2O2 and 8.8×10-8mol/L for resveratrol. The system was successfully employed to value the gross activity of antioxidants of peanut using resveratrol as the index. The results suggested a good recovery within the range from 88.8% to 109.1%.