CdTe量子点双层加壳增强其化学和生物稳定性

Dual-Silica-Coated CdTe Quantum Dots with Enhanced Chemical Stability and Biostability

为改善量子点在生物环境影像对氧化还原环境和金属离子的耐受性,使量子点适用于超长时间实时影像,使用改良的Stober方法对量子点分别进行了氨基硅烷化试剂和硅烷化试剂2次水解加壳,并利用热稳定为衡量指标优化了加壳条件.结果表明:双层加壳的量子点对铁、亚铁离子、高离子强度环境和氧化还原环境获得了很好的耐受性.双层加壳后量子点模拟用于超长时间实时荧光影像监测发现:与金黄色葡萄球菌共培养荧光可持续保留168 h,较未包壳量子点提高了14倍;与大肠杆菌共培养荧光可持续保留48h,较未包壳量子点提高了6倍.

In order to improve the tolerances of quantum dots （QDs） to metal ions and redox environment for application in long time imaging, CdTe QDs were modified by Stober＇s method, which coated silica and amino functioned silica onto the nanoparticles respectively. Thermal stability was monitored to optimize the coating conditions. The results showed that the dual-silica-coated quantum dots were highly stable against ions, high ionic strength and redox environment. When applied in simulated real-time ultra-long time fluorescence imaging, the fluorescence of dual-silica-coated quantum dots culturing with Staphylococcus aureus sustained for 168 h , 14-fold increased compared with uncoated QDs, while the fluorescence sustained for 48 h when cultured with E. coli, increased 6-fold.