Analytical Sciences

Abstract − Analytical Sciences, 28(3), 267 (2012).

Enhanced Electrochemiluminescence Employed for the Selective Detection of Methyl Parathion Based on a Zirconia Nanoparticle Film Modified Electrode
Hankun ZHOU, Ning GAN, Jianguo HOU, Tianhua LI, and Yuting CAO
The State Key Laboratory Base of Novel Functional Materials and Preparation Science, Faculty of Material Science and Chemical Engineering of Ningbo University, Ningbo 315211, China
A simple, rapid and sensitive electrochemiluminescence (ECL) sensor was proposed for direct measurements of methyl parathion (MP) based on the strong affinity of a nano zirconia particles (ZrO2 NPs) modified film on the electrode to the phosphoric group. ZrO2 NPs, which could provide a larger absorption area to immobilize organophosphorus, was firstly modified on the glassy carbon electrode surface to prepare the proposed ECL sensor (ZrO2/GC). Subsequently, the ZrO2/GC electrode was scanned from –0.8 to +0.6 V to obtain the background signal at 0.44 V in a luminol/KCl solution. Then, a certain concentration of MP was added to an aqueous solution for 240 s, which was absorbed onto the ZrO2/GC electrode surface. Moreover, the MP absorbed on the surface of the ZrO2/GC electrode enhanced the ECL signal of luminol in the luminol/KCl solution, which increased with the concentration of MP. As a result, a novel ECL sensor was obtained in a luminol/KCl solution. The MP was determined in the range of from 3.8 × 10−11 to 3.8 × 10−6 mol L−1, with a low detection limit of 1.27 × 10−11 mol L−1 (S/N = 3). The proposed ECL sensor performance for MP detection will open a new field in the application of rapid and screen detection of ultra-trace amounts of organ phosphorus pesticides (OPs) of vegetables used in farm markets.