Colorimetric determination of iodine based on highly selective and sensitive anti-aggregation assay

Abstract

Iodine as a mineral has great effects on public health; accordingly, there has been an urgent request for iodine selective and sensitive sensor. A colorimetric assay based on the anti-aggregation exclusive feature of gold nanoparticles is presented in this study. The proffered sensor was manufactured in regard to the interaction between thiosulfate and gold nanoparticles, and the forceful inactivation of thiosulfate by iodine. Different concentrations of iodine lead to differential inactivation of thiosulfate, which is in charge of obvious color alteration of AuNPs from blue to red. The quantification of iodine is acquired in relation to the alteration in the surface plasmon resonance absorption of the gold nanoparticles. Under the optimum condition, the limit of detection is 1.36 nmol L−1 with the linear range from 3 to 80 nmol L−1. Further utilization of the proposed colorimetric method to determine iodine in human serum presented satisfying consequence concerning selectivity and sensitivity.