量子点碲化镉和银纳米粒子双组分修饰聚苯乙烯微球的荧光和SERS应用.docVIP

  量子点碲化镉和银纳米粒子双组分修饰聚 苯乙烯微球的荧光和 SERS 应用# 沈姗姗，栾昕彤，王海阳，姜灿卫，董凤霞，宋薇，王旭，赵冰，阮伟东** 5 10 15 20 25 30 （吉林大学超分子结构与材料国家重点实验室，长春 130012） 摘要：量子点因具备激发光谱线选择性多、发射强度高、荧光效率好以及发射光谱窄等特性 被广泛研究，并应用于生物标记领域。在各种量子点中，碲化镉量子点（CdTe QDs）是最 基础也是最重要的一种。本文介绍一种省时、廉价、灵活的方法，用于制备双组分修饰的聚 苯乙烯（PS）微球。将功能化的 PS 微球作为底物，利用层层自组装技术，通过静电相互作 用将 CdTe QDs 和银纳米粒子（Ag NPs）组装到 PS 微球的表面。由于 CdTe QDs 和 Ag NPs 的存在，复合的微球既具有表面增强拉曼散射（SERS）性能，又具有荧光性能，可应用于 食品安全监测、生物标记、环境污染物检测以及医疗成像等方面。 关键词：物理化学；表面增强拉曼散射；量子点；荧光；自组装 中图分类号：O64 CdTe quantum dots and Ag nanoparticles modified polystyrene microspheres: Applications both in fluorescence and in SERS SHEN Shanshan, LUAN Xintong, WANG Haiyang, JIANG Canwei, DONG Fengxia, SONG Wei, WANG Xu, ZHAO Bing, RUAN Weidong (State Key Laboratory of Supramolecular Structure and Materials, Jilin University, Changchun 130012) Abstract: Due to the multiple excitation line selectivity, high emission intensity, high fluorescence efficiency and narrow emission characteristics of quantum dots (QDs), the QDs have been studied extensively and applied to the field of biomarkers. In a variety of QDs, CdTe QDs is the most basic and important one. This paper will introduce a time-saving, inexpensive and flexible method for the preparation of two-component modified polystyrene (PS) colloidal microspheres. The negatively-charged CdTe QDs and Ag nanoparticles (NPs) were deposited on the PS microspheres through a media layer of positively-charged polyelectrolyte via the layer-by-layer self-assembly technique. As the dually modified composite microspheres have both surface-enhanced Raman scattering (SERS) performance and fluorescence property, they can be applied in food safety detection, biological identification, environmental pollutant detection and medical imaging. Key words: Physical chemistry; SERS; Quantum Dots; Fluorescence; Self-assembly 35 0 引言 表面增强拉曼散射（SERS）因具有灵敏性高、光谱选择性强、检测无损等特性，已经 成为一种快速发展的光谱技术。对于 SERS 技术而言，最重要的是基底材料的选择和制备。 贵金属纳米粒子是最常用的 SERS 基底，其中最典型的就是金纳米粒子（Au NPs）和银纳米 40 粒子（Ag NPs）。直到现在，以 Au NPs