Sensitive Homogeneous Electrochemical Detection of Organophosphorus Pesticides by UiO-66-NH2 Embedded with a
Chaofeng Zhang1, Yinhui Yi1, Yong Zhao2
1School of the Environment and Safety Engineering, Key Laboratory of Zhenjiang, and Collaborative Innovation Center of Technology and Material of Water Treatment, Jiangsu University, Zhenjiang 212013, P. R. China.
Abstract:
This study prepared UiO-66-NH2 MOFs embedded with Ru-tris(2,2'-bipyridyl)(II) hybrids as a nanozyme (designated as Ru/UiO-66-NH2) to propose a bioenzyme-free homogeneous electrochemical (HEC) sensing strategy for detecting organophosphorus pesticides (OPs). Experimental investigation coupled with density functional theory calculation demonstrated that the Ru incorporation significantly amplifies the peroxidase-like (POD-like) activity of UiO-66-NH2 MOFs and that the Ru/UiO-66-NH2 nanozyme exhibits selective responsiveness to coordinate with the OP molecules. Upon OP exposure, the specifical coordination between OPs and MOF structure effectively inhibits the nanozyme's activity. Utilizing o-phenylenediamine as the catalytic substrate and glyphosate as a model of OPs, the optimized HEC sensor achieves an extensive linear detection range (0.5-10,000 ng/mL) and a low detection limit of 0.13 ng/mL as well as satisfactory recoveries in the real samples of tomato extract and water. It is expected that this innovative bioenzyme-free HEC sensing strategy represents a promising advancement for practical OP residue analysis with potential applications in various fields.
