Wang Xiaohui, Li Yan, Du Yumin
College of Resource and Environmental Science, Wuhan University, Wuhan 430079, China.
J Nanosci Nanotechnol. 2009 Dec;9(12):6866-75. doi: 10.1166/jnn.2009.1889.
Water-soluble biocompatible and monodisperse ZnS, CdS, CdSe quantum dots (QDs) were synthesized using natural chitosan derivatives as stabilizers. TEM, XRD, SAED and UV-vis confirmed the formation of nanoparticles with average size of 3-5 nm, and the resulted ZnS, CdS nanocrystals were shown to be of cubic and blended phase. It was found that the molecular structure of chitosan stabilizer had a large influence on the optical and crystalline properties of the QDs. Through refluxing, the surface defects of the nanoparticles were passivated and the photoluminescence were enhanced. The particle size and the photoluminescence intensity can be controlled through altering the concentration of precursor ions and stabilizer solution, the molar ratio of metal ions/[S2-] and refluxing time. The resulting biopolymer/QD composite can be potentially applied as biosensor or fluorescence tags in biological systems.
以天然壳聚糖衍生物为稳定剂，合成了水溶性生物相容性单分散硫化锌、硫化镉、硒化镉量子点（QDs）。透射电子显微镜（TEM）、X射线衍射（XRD）、选区电子衍射（SAED）和紫外可见光谱证实形成了平均尺寸为3 - 5纳米的纳米颗粒，所得硫化锌、硫化镉纳米晶体显示为立方相和混合相。研究发现壳聚糖稳定剂的分子结构对量子点的光学和晶体性质有很大影响。通过回流，纳米颗粒的表面缺陷被钝化，光致发光增强。通过改变前驱体离子和稳定剂溶液的浓度、金属离子/[S2-]的摩尔比以及回流时间，可以控制粒径和光致发光强度。所得生物聚合物/量子点复合材料有望作为生物传感器或荧光标记物应用于生物系统。
