Development of a Novel Fluorescence Nanoprobe Based on Molecularly Imprinted Polymer on Cobalt-Carbon Quantum Dots for Rapid Detection of Methamphetamine

In forensic drug analysis, detecting low concentrations of illicit drugs in samples presents a significant challenge. This paper introduces a novel approach for developing molecularly imprinted quantum dot materials (Co-AD QDs-MIPs) capable of efficiently detecting methamphetamine (METH) in artificial urine without the need for extraction or pretreatment. Using free radical polymerization, molecularly imprinted materials were coated onto the surface of quantum dots, forming a Co-AD QDs-MIPs fluorescence nanoprobe. The resulting Co-AD QDs-MIPs demonstrated enhanced specificity for METH detection and showed strong fluorescence quenching. Under optimal conditions, the method enabled selective and quantitative detection of METH. A good linear correlation was observed between the fluorescence quenching effect and increasing METH concentration in the range of 67–469 nM, with a detection limit of 23 nM. The Co-AD QDs-MIPs nanoprobe successfully detected METH in simulated human urine samples, with a recovery rate of 96.2% to 102.1%. Therefore, it is a simple, cost-effective, and selective nanoprobe for detecting low concentrations of METH.