水相分散的纳米晶/聚合物点二元荧光复合微球的制备

Due to the simple preparation, controllable fluorescent color, the small particle size, and the multi-composite function, the nanocrystals (NCs) and its composition are considered as an excellent probe materail in biology labeling, molecule detection, controlled release and so on. This project intends to prepare a NCs/polymer composite microsphere by self-assemble between the NCs and amphiphilic copolymer according to the hydrophobic - hydrophobic interaction. Then the shell polymers of the microspheres in situ change to be luminescent polymer dots (PDs) by some inductions, and the NCs/polymer dots binary fluorescent composite microspheres are obtained. This new carbon composite microsphere will greatly improve the stability and biocompatibility compared to NCs, and possesses two fluorescent units. This new, green and multiple response, fluorescent composite material will provide new ideas and methods in tracing cell lable, specific molecular detection etc.

荧光纳米晶及其复合材料由于其简单的制备方法、可控的荧光颜色、较小的粒子尺寸，多元的复合功能，被认为是优良的探针材料，广泛应用于物标记、分子检测、可控释放等领域。本项目拟利用分子间疏水-疏水相互作用，使两亲性聚合物与荧光纳米晶发生组装，得到纳米晶/聚合物复合微球，再通过多种诱导方法，使复合微球壳层的聚合物原位转化为荧光聚合物点，从而制得纳米晶/聚合物点二元荧光纳米复合微球。这种壳层主要为碳材料的新型荧光复合微球，其稳定性和生物相容性较纳米晶大大提高，并且含有两种荧光发色物质，因此是一种新型、绿色、多重响应的荧光复合材料，将在细胞示踪标记、特异分子检测等方面提供新思路和手段。

荧光材料由于其广泛的荧光发射波长、可调的微观尺寸、简单的制备工艺、多样的结构功能被广泛应用在分子检测、生物标记、可控释放等领域。本项目利用马来酸酐-1-十八烯交替共聚物和乙二胺为原料，一步水热法制备了一种两亲性聚合物荧光碳点，而后再通过疏水疏水相互作用将其与半导体纳米晶进行复合，得到了二元荧光复合微球。这种二元荧光复合微球良好地保持了原材料中的荧光性质，实现了荧光性质的集成。通过改变复合条件，二元荧光复合微球的荧光颜色可以实现从蓝光到红光的连续调控。该二元荧光复合微球对Hg2+离子有特异性响应，由于体系中存在荧光共振能量转移，是荧光检测的灵敏度大大增加，其光谱检测限为10nM，肉眼可视检测限为100nM。这种聚合物荧光碳点与纳米粒子的复合方法具有操作简单，材料普适等优点，为其它功能纳米粒子与聚合物荧光碳点复合材料的制备提供了新思路。