量子点的制备及其与葡萄球菌蛋白A偶联条件的优化

Preparation of cadmium telluride quantum dots and optimization of the coupling conditions with Staphylococcal protein A

目的:制备量子点与葡萄球菌蛋白A(Staphylococcal protein A,SPA)的偶联物,探究偶联反应的最佳条件。方法:采用“经典注入法”制备碲化镉量子点,使用1-乙基-3-(3-二甲氨基丙基)碳二亚胺盐酸盐(EDC)和N-羟基丁二酰亚胺(NHS)作为偶联剂用于偶联量子点和SPA,采用单因素考察法,分别探究EDC、NHS和SPA用量以及反应时间对偶联效率的影响。结果:制备得到不同量子点、EDC、NHS、SPA比例以及不同反应时间的偶联物,其中量子点和EDC的比例为1∶1500,EDC和NHS的比例为1∶2,反应时间为2 h时偶联物荧光强度最强。结论:碲化镉量子点∶EDC∶NHS为1∶1500∶3000,反应时间为2 h时,可以制备出荧光强度较好的量子点SPA偶联物。

Objective:To prepare conjugates of quantum dots and Staphylococcal protein A(SPA)and figure out the optimal conditions.Methods:The“classical injection method”was used to prepare cadmium telluride quantum dots,while 1-ethyl-3-(3-dimethyl aminopropyl)carbodiimide(EDC)and N-hydroxysuccinimide(NHS)were applied as coupling agents for coupling quantum dots with SPA.A single factor inspection method was adopted to explore the effects of the different amount of EDC,NHS,SPA and the reaction time on the coupling efficiency.Results:A series of conjugates were prepared with different ratios of quantum dots,EDC,NHS,SPA and reaction time.Among them,the fluorescence intensity of the conjugate is the strongest while the ratio of quantum dots to EDC is 1∶1500,the ratio of EDC to NHS is 1∶2,and the reaction time is 2 h.Conclusion:When the ratio of cadmium telluride quantum dots to EDC and NHS is 1∶1500∶3000,and the reaction time is 2 h,the cadmium telluride quantum dot-SPA conjugate with better fluorescence intensity could be prepared.