Ultrasensitive and rapid electrochemical detection of nitrite based on gold nanoparticles-poly(phenylboronic acid) modified electrode and I2/I- probe.

Abstract

A novel electrochemical sensor based on gold nanoparticles-poly(phenylboronic acid)/glass carbon electrode (AuNPs-poly(PBA)/GCE) was successfully constructed for detecting nitrite (NO2-) ions using the iodine/iodide (I2/I-) mixed system as a probe. The AuNPs-poly(PBA) composites were firstly prepared on a bare GCE by one-step electrodeposition. By combining the specific enrichment ability of poly(PBA) to NO2- and I2/I- with the catalytic activity of AuNPs to the reaction between them, the response range of this sensor towards NO2- was 1.0 × 10-11 M to 1.0 × 10-4 M with a limit of detection (LOD) of 1.7 × 10-12 M (S/N = 3). The sensor had the advantages of easy preparation, fast response, wide linear range, low LOD, and good selectivity, and could be applied to detect NO2- in beef and tap water samples with satisfactory results, which provided a highly sensitive and rapid analysis approach in the fields of food safety and environmental monitoring.