CdTe量子点分子印迹传感器对水中磺胺类药物残留的检测

磺胺类抗生素被广泛应用于水产养殖,会对环境造成危害。为了检测水环境中该类药物的浓度,本研究合成了磺胺类药物量子点分子印迹传感器,用于快速检测水样中的磺胺类抗生素。在CdTe量子点表面,以磺胺嘧啶为虚拟模板,采用溶胶-凝胶法合成了具有良好光学性质的分子印迹荧光传感器。通过红外光谱(FT-IR)、透射电子显微镜(TEM)和扫描电子显微镜(SEM)对传感器进行了表征,并测试了pH值对测定条件的影响,分析了传感器对不同药物的选择性。印迹聚合物成功接枝在了量子点表面,在pH为8.0时,具有最佳荧光吸收。在该条件下,当磺胺嘧啶在2~10μmol/L的浓度范围内,CdTe@SiO2@MIPs的荧光猝灭率(F0/F)随体系中磺胺嘧啶的浓度变化关系符合SternVolmer方程(R2=0.982 7,n=5)。加标回收率显示,磺胺嘧啶的回收率范围为90.0%~104.4%,相对标准偏差不超过14.7%。实验结果表明制备的CdTe@SiO_2@MIPs可快速灵敏地检测水样中磺胺类药物的残留。

Molecularly imprinted based on CdTe quantum dots for the determination of sulfonamide residues in water

Sulfonamides are widely used in aquaculture and pose a hazard to the environment. In order to detect the concentration of such drugs in the water environment, this study synthesized a sulfa drug quantum dot molecular imprinting sensor for rapid detection of sulfa antibiotics in water samples. On the surface of CdTe quantum dots, a molecularly imprinted fluorescent sensor with good optical properties was synthesized by the sol-gel method using sulfadiazine as a dummy template. Characterization of the polymers was conducted by infrared spectroscopy, transmission electron microscopy, and scanning electron microscope, and showed that the imprinted polymer was successfully grafted onto the surface of the quantum dots. Selectivity of CdTe@SiO₂@MIPs was explored through experiments. Under optimal conditions, the FL quenching in this system followed the Stern-Volmer equation(R²=0.982 7,n=5) when the concentration of sulfonamide was in the range of 2-10 μmol·L^-1. The actual sample measurement displayed that recoveries of sulfonamide were between 90.0 and 104.4% with satisfactory precision RSD lower than 14.7% in all cases. The proposed MIP-QD method provides a tool for rapid and sensitive determination of sulfonamide in water samples.