牛血清蛋白修饰的CdTe量子点作为铜离子检测探针的实验研究  

Experimental Study on Application of Bovine Serum Albumin Modified CdTe Quantum Dots as Detective Probe for Cupric Ions

作　　者：郑元青[1] 李丹[1] 孔翰[1] 童春义[1] 刘选明[1] 

机构地区：[1]湖南大学生命科学与技术研究院,湖南长沙410082

出　　处：《工业卫生与职业病》2009年第4期193-197,共5页Industrial Health and Occupational Diseases

基　　金：国家高校"985工程"创新平台项目

摘　　要：目的探讨采用牛血清蛋白（BSA）修饰的水溶性碲化镉（CdTe）量子点作为荧光探针,基于荧光猝灭法建立了一种更为灵敏的铜离子检测体系。方法实验首先考察了缓冲液pH值、反应时间、铜离子浓度等因素对量子点荧光强度的影响,进一步比较了经BSA修饰的CdTe量子点与纯CdTe量子点在荧光特性以及对铜离子的响应情况等方面的差异,同时还采用铜离子反向测定量子点浓度的方法进行验证。结果在pH值为7.3的磷酸盐缓冲液中,当反应时间为20 min时,经BSA修饰过的CdTe量子点对铜离子的亲和性得到了增强,对铜离子浓度的依赖性更明显,分辨率更高。其发生荧光猝灭的线性范围为6.4-518.4μg/L,线性回归方程为△F（F0/F）=1.0497＋0.0073c（μg/L）,线性相关系数为R=0.9716。并且当用铜离子反向测定量子点浓度时,在一定范围内也同样呈现出良好的线性关系。结论BSA修饰的CdTe量子点有可能成为检测铜离子的更好探针。Objective Water-soluble CdTe quantum dots （QDs） were modified with bovine serum albumin （BSA） and used as the fluorescence probe. Based on fluorescence quenching method, a sensitive approach was developed for the determination of copper ions with quantum dots. Methods Different influencing factors were studied, including pH of the buffer solution, reacting time and the concentration of copper ions. The differences in fluorescence properties between pure CdTe QDs and BSA modified CdTe QDs and their responses from copper ions were compared. At the same time, the method of reversely detecting the concentration of quantum dots using copper ions was verified. Results In pH 7.3 phosphate buffer solution and under 20 rain reacting time, the affinity of BSA modified CdTe QDs to copper ions was strengthened, the dependence to the concentration of copper ions became more obvious and the resolution became higher. The relative fluorescence intensity was linearly proportional to the concentration of copper ions in the range of 6.4 to 518.4 μg/l. The linear regression equation was △F（Fo/F） =1. 0497 ＋0. 0073C（μg/L）, and the linear relative parameter was R = 0. 9716. Moreover, when the QDs concentration was determined reversely by copper ions, in certain range good linear relationship was also shown. Conclusions BSA modified CdTe QDs might become a better probe for detecting trace amounts of copper ions than pure CdTe QDs.

关 键 词：量子点 铜离子 荧光猝灭 

分 类 号：R115[医药卫生—公共卫生与预防医学]