基于CdTe量子点和磁性纳米材料构建的夹心型电化学免疫传感器

目的 制备新型夹心型电化学免疫传感器,并研究该传感器的性能. 方法 以甲胎蛋白（AFP）作为检测模型,以磁性微球为一抗固定载体,CdTe量子点作为二抗标记物,通过碳二亚胺交联法制备AFP一抗固化的免疫磁珠和AFP二抗固化的CdTe量子点,通过夹心免疫分析模式和电化学溶出伏安法建立新型高灵敏电化学免疫传感器,并采用红外光谱、紫外光谱及电化学方法对该传感器进行表征. 结果 该电化学免疫传感器对AFP抗原检测的线性范围为1～200 ng/mL,检测限为0.025 ng/mL. 结论 该电化学免疫传感器仪器简单、操作便捷、检测结果稳定,并具有较高的灵敏度.

Electrochemical Immunosensor Based on CdTe Quantum Dots and Magnetic Nanoparticles

Objective A novel sandwich electrochemical immunosensor has been developed by taking alpha fetal protein （AFP）as the detection model,and using magnetic microspheres as the immobilized carrier of the primary AFP antibody and CdTe quantum dots as the secondary antibody label,and the per formance of the immunosensor has been studied.Methods The primary AFP antibody immobilized immunomagnetic beads and the secondary AFP antibody immobilized CdTe quantum dots were prepared by carbodiimide crosslinking method.A novel high sensitivity electrochemical immunosensor has been developed by sandwich immunoassay and electrochemical stripping voltammetry.In addition,the characteristics of the immunosensor were investigated by using the infrared spectroscopy,ultraviolet spectrum and electrochemical methods,respectively.Results The electrochemical immunosensor exhibited a wide linear range from 1 to 200 ng/mL with a low detection limit of 0.025 ng/mL at signal to noise ratio of 3.Conclusion This electrochemical immunosensor based on CdTe quantum dots and magnetic nanoparticles for the detection of AFP is easy,convenient,inexpensive,stable,and shows good stability and high sensitivity.