Molecularly Imprinted Polymer Electrochemiluminescence Sensor Based on AuNPs@Ru-ZIF8 for Cyhalothrin Residues Rapid Detection in <em>Lycium barbarum L.</em>

Lycium barbarum L. is widely used medicinal and edible Chinese medicinal materials. However, with consumers' heightened concern for health and food safety, pesticide residues have become one of the major challenges affecting its’ quality and safety. cyhalothrin is a pyrethroid insecticide, and is a typical type of pesticide with excessive pesticide residues in Lycium barbarum L. Rapid detection of pesticide residues is an effective way to ensure the quality and safety of traditional Chinese medicinal materials. In this work, a molecularly imprinted polymer electrochemiluminescence (ECL) sensor based on AuNPs@Ru-ZIF8 was constructed for cyhalothrin residues rapid detection. The prepared cyhalothrin molecularly imprinted polymer (MIPs) was used as a recognition element and modified onto the surface of GCE by electrochemical polymerization method. Gold nanoparticle (AuNPs) were utilized to promote the excitation of Ru(bpy)32+ and TPrA in the ECL system, which improved the observability of the light signal. The glassy carbon electrode(GCE) modified with the Metal Organic Frameworks ZIF8 was utilized to increase the specific surface area and thus improve the sensitivity of the sensor. In addition, the luminescent reagent Ru(bpy)32+ was introduced into the synthesis process of ZIF8, which caused Ru(bpy)32+ to be tightly bound around it and enhanced the stability of the sensor. Under optimal conditions, the linear detection range of the sensor is 1 × 10-1~1 × 104 nM, with a minimum detection limit (LOD) of 10 pM. The accuracy of the ECL MIPs sensor has been verified through spiked recovery experiments and actual sample testing. This study has opened up a new approach for rapid detection of pesticide residues in traditional medicinal herbs used for both food and medicine.