制备了以二硫基琥珀酰亚胺丙酸酯,4-巯基苯硼酸功能化CdTe量子点探针,对其进行了X-射线光电子能谱和透射电镜表征。在431nm激发波长下,对探针及加入多巴胺后进行发射光谱扫描,最大发射峰红移,在最大发射波长处,多巴胺对合成的探针具有猝灭效应,且多巴胺对体系的猝灭程度与多巴胺的量呈良好的线性关系,据此建立了一种直接、灵敏、选择性好的测定多巴胺的方法。在最佳条件下,多巴胺的其线性范围为0.02-20.0μmol/L,线性回归方程为△F-20.1+31.7C(gmol/L),相关系数为R^2=0.987,检出限为4.9nmol/L。本方法已成功用于多巴胺注射液、血清及尿样中多巴胺的测定,结果满意。
CdTe quantum dots probe with both 4-mercaptophenylboronic acid and dithiobis(succinimidylpropionate) was designed and functionalized, and characterized by XPS and TEM. Emission spectra of CdTe quantum dots probe and dopamine was scanned under 431 nm excitation wavelength. The maximum emission wavelength shift red. At the maximum emission wavelength, dopamine results in fluorescence quenching of the probe. A direct, selective, and sensitive strategy for the determination of dopamine was established. The effects of determination conditions were investigated. Under the optimal conditions, a good linearity (R^2 =0. 987) was obtained between fluorescence intensity and dopamine concentration in the range of 0.02-20.0μmol/L. The linear regression equation was △F= 20.1+31.7C(μmol/L). The limit of detection was 0. 0049μmol/L. The method has been successfully applied to determine dopamine in injection, serous and urine with satisfactory result.