A novel optical sensor based on carbon dots embedded molecularly imprinted silica for selective acetamiprid detection.

Abstract

A molecularly imprinted polymer (MIP) on silane-doped carbon dots (Si-CDs) has been synthesized as a novel optical sensor for selective detection of acetamiprid (ACT). Highly fluorescence Si-CDs have been first prepared by hydrothermal method. Subsequently, MIP has been formed on the surface of Si-CDs (MIP@Si-CDs) by a sol-gel process. The properties and structure of the Si-CDs and MIP@Si-CD nanocomposites have been characterized by fluorescence spectroscopy, UV-Vis absorption spectroscopy, transmission electron microscopy, dynamic light scattering, Fourier transform infrared spectroscopy, and X-ray diffraction techniques. Various parameters, which affect the optical signal, have been optimized. The fluorescence signal of MIP@Si-CDs showed linear response with ACT concentration in the 7-107 nM range with a detection limit of 2 nM and a precision of 2.7% and 3.3% for five replicate detections of 17 and 33 nM ACT under optimal conditions. In addition, the sensor has been satisfactorily utilized for the detection of ACT content in real samples.