牛血清白蛋白修饰水溶性CdTe量子点及分析应用

Surface-Modification of CdTe Quantum Dots with Bovine Serum Albumin and Analytical Application

以巯基乙酸为稳定剂,采用水热法合成了CdTe量子点,用牛血清白蛋白改变量子点的表面修饰状态并通过荧光发射光谱研究了溶液pH、温度和离子强度对表面修饰产生的影响.结果表明,CdTe量子点在502 nm处有吸收,在538 nm处有荧光发射,经牛血清白蛋白对其表面修饰后,吸收峰位不变,但吸光强度升高;荧光发射峰位不变,荧光显著增强.在优化的反应条件下,牛血清白蛋白质量浓度在0.05～1.0 mg/L范围内与荧光增加值呈线性关系,检出限为0.011 7 mg/L。以缓冲溶液为基底牛血清白蛋白含量测定获得满意结果.

Mercaptoacetic acid-stabilized CdTe quantum dots were prepared by hydrothermal synthesis method.The CdTe quantum dots exhibited absorption at 502 nm and fluorescence emission at 538 nm,respectively.When surface-modification of CdTe quantum dots were replaced with BSA,absorption peak and the fluorescence peak remained the same,while absorption intensity and the fluorescence emission intensity increased.The effect of pH、temperature and ion strength on fluorescence intensity were discussed.Under the optimal conditions,a mass concentration of BSA in the range of 0.05～1.0 mg/L shows a linear relationship with the fluorescence intensity increasing value of CdTe quantum dots,with a detection limit of 0.011 7 mg/L.The proposed method was applied to detection of the concentration of BSA in buffer solution.