水溶性硅包CdTe量子点的合成方法研究（英文）

Synthesis of aqueous silica-coated CdTe quantum dots

本研究成功地合成了水溶性CdTe量子点（QDs）.考察温度对回流时间、荧光强度及粒径大小等因素的影响,实验优化合成条件之后确定最佳反应温度为105℃.接着,本研究运用改进后的Stober法更为简易地合成了硅包CdTe量子点复合微球,该微球的粒径可通过改变正硅酸乙酯及水的含量控制在160~260nm之间,同时根据复合微粒的电镜拍摄图初步探讨了SiO2在CdTe表面的生长模式.为了将来能运用到生物检测中,此实验加入3-氨基丙基三乙氧基硅烷（APTS）,引入氨基团,并优化了APTS加入时间,得到的粒子表面氨基含量最高.这种复合微粒具有与原来量子点相当的量子产率,同时具有良好的水溶性、胶体稳定性、化学反应性,为量子点作为荧光标记物的应用打下了基础.

In this study,the water-soluble CdTe quantum dots（ QDs） had been successfully synthesized. The temperature at 105 ℃ had been determined to be the optimum condition by considering the refluxing time,the fluorescence intensity and the diameter distribution. A modified Stober Method for the facile synthesis of CdTe@SiO_2 composite particles was also presented in this article. The diameter of composite particles could be easily tuned between 160 nm and 260 nm by changing the rate of Tetraethylorthosilicate（ TEOS） and water. We also conjectured the growth pattern of SiO_2 on the surface of Cd Te QDs according to TEM images. Considering the further applications in biological detection,3-aminopropyltriethoxysilanes（ APTS） had been introduced to enhance abundant amine groups on the surface of silica shell and the perfect time had been also confirmed to add it in the view of crystal growth theory. Based on the above,the content of amino on particles surface is the highest. These composite microspheres have better water solubility,stability,and reactivity compared with original QDs. It sets the stage for the application of QDs as fluorescent probes.