化学学报 ›› 2012, Vol. 70 ›› Issue (06): 789-795.DOI: 10.6023/A1106173 上一篇    下一篇

研究论文

亲水性修饰的量子点的结构对荧光性能的影响研究

孔珺a, 邱涵a, 余敏a, 张兵波b   

  1. a 华中科技大学同济医学院附属荆州医院乳腺科 荆州 434100;
    b 同济大学先进材料与纳米生物医学研究院 上海 200092
  • 投稿日期:2011-06-17 修回日期:2011-09-30 发布日期:2011-11-22
  • 通讯作者: 张兵波
  • 基金资助:

    国家自然科学基金(Nos. 51003078, 81171393)、同济大学青年优秀人才培养计划(No. 2009KJ072)和同济大学青年英才计划(优秀青年教师)资助项目.

Effect of Structure on the Fluorescent Properties of the Hydrophilic Modified Quantum Dots

Kong Juna, Qiu Hana, Yu Mina, Zhang Bingbob   

  1. a Jingzhou Hospital Affiliated with Tongji Medical College, Huazhong University of Science and Technology, Jingzhou 434100;
    b The Institute for Advanced Materials & Nano Biomedicine, Tongji University, Shanghai 200092
  • Received:2011-06-17 Revised:2011-09-30 Published:2011-11-22
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Nos. 51003078, 81171393), Program for Young Excellent Talents in Tongji University (No. 2009KJ072) and Program for Outstanding Young Teachers in Tongji University.

亲水性量子点的荧光性能是其作为生物检测探针的一个重要质量指标. 不同结构的量子点在亲水性修饰过程中, 其抵抗荧光淬灭的能力差异较大. 设计与制备具有不同结构和成分的核、核壳量子点, 再通过双亲性高分子对其亲水性改性, 利用荧光光谱监测亲水性修饰过程中的荧光性能变化来度量所合成量子点的光化学稳定性. 实验结果表明,在表面亲水性修饰过程中, 未包覆壳层的裸核量子点其抵抗荧光淬灭的能力最弱; 包覆壳层的核壳量子点, 其抵抗荧光淬灭的能力增强, 且壳层越多, 抵抗能力越强. 壳层的结构和成分直接影响核壳量子点抵抗荧光淬灭的能力, 具有合理晶格匹配的核壳量子点, 其抵抗荧光淬灭的能力较强. 另外, 通过优化设计与制备的核壳量子点经表面亲水性修饰后, 再偶联叶酸, 构建出特异性生物荧光探针, 对乳腺癌细胞进行靶向性标记后, 利用流式细胞仪进行细胞检测分析. 实验结果表明, 通过优化制备的核壳量子点, 亲水性修饰后仍具有很好的荧光性能, 偶联叶酸后具有较好的细胞靶向性.

关键词: 量子点, 亲水性修饰, 荧光性能, 核壳结构, 细胞靶向

Quantum dots (QDs), as a new class of biological nanoprobe, its fluorescence properties are related to the detection sensitivity. QDs with different core-shell structures vary in the resistance to the fluorescence quenching during surface modification. In this study, a series of core and core-shell QDs with different structure and composition were designed and synthesized. And they were modified with amphiphilic polymer. Their fluorescence properties during the surface modification were monitored by fluorescence spectroscopy. Experimental results show core QDs are the most easily quenched during the surface modification; the ability of resistance to quenching is enhanced after shell coating on core QDs, and this ability increases with the shell layers increase. Results also indicate the structure and composition of shells affect the resistance to fluorescence quenching. The resistance to fluorescence quenching is greatly enhanced when the core-shell QDs has a reasonable shell structure and composition. Furthermore, specific QD nanoprobes are constructed based on selecting appropriate structure of QDs and coupling with folic acid. The prepared QD nanoprobes are used for detection of breast cancer cells on flow cytometry. The results show that by optimizing the structure of core-shell QDs, the modified hydrophilic QDs have good fluorescence property. And the optimized hydrophilic QDs coupled with folic acid have targeting capability of cancer cells.

Key words: quantum dots, hydrophilic modification, fluorescence property, core-shell structure, cell targeting