A highly selective fluorescence nanosensor based on the dual-function molecularly imprinted layer coated quantum dots for the sensitive detection of diethylstilbestrol/cypermethrin in fish and seawater

The surface molecularly imprinted layer coated CdSe/CdS/ZnS quantum dots (MIP-CdSe/CdS/ZnS QDs) was developed and utilized as the selective optosensing materials of the fluorescence nanosensor to diethylstilbestrol (DES) and cypermethrin (CYP), respectively. The surface morphology, functional group and fluorescence spectroscopy were conducted to demonstrate the fluorescence quenching response of MIP-CdSe/CdS/ZnS QDs to DES/CYP. Under their individual optimal conditions, good linear relationships for DES and CYP were observed in the range of 0.050–20.0 mg/L and 0.10–20.0 mg/L. In addition, the recoveries reached a satisfactory level of 91.4%–101.5 % with an RSD value less than 5.4 % for the samples of seawater and fish. The corresponding limits of detection in seawater and fish can reach 0.004 μg/L and 3.0 μg/kg (DES), and 0.3 μg/L and 5.0 μg/kg (CYP). This study provided a general strategy for fabricating an efficient fluorescence nanosensor based on a dual-template MIP-CdSe/CdS/ZnS QDs to selectively detect different analytes in their individual optimum conditions.