含螺吡喃端基PNIPAM的制备及其在活细胞成像中的应用

Preparation of Spiropyran-Terminated PNIPAM for Fluorescence Imaging of Live Cells

利用ATRP活性聚合制备了不同分子量的含有螺吡喃(SP)端基的聚(N-异丙基丙烯酰胺)(SP-PNIPAM)。考察了SP-PNIPAM的光致变色性能、荧光性能和临界转变温度,并研究了它们在活细胞成像方面的应用。螺吡喃以及SP-PNIPAM经激发后发射红色荧光。螺吡喃可以通过扩散穿过细胞膜进入细胞,因而对固定、成活细胞均能染色。而SP-PNIPAM用于细胞染色时,其染色特性与分子量有关,主要通过活细胞内吞作用进入活细胞内,因此可以选择性地用于活细胞荧光成像。

Spiropyran-terminated poly（N-isopropylacrylamide） （SP-PNIPAM） with different molecular weights were prepared by atom transfer radical polymerization. Their photochromic property, fluorescence property and critical transition temperature were investigated. SP-PN1PAM was tested as polymer dyes for cell fluorescence imaging. SP and SP-PNIPAM emitted red fluorescence if excited. Spiropyran could diffuse through the cell membrane into the cell, and thus fixed and living cells could be stained. When being used as fluorescence dyes for cell imaging, the dye performances of SP-PNIPAM depended on their molecular weights. SP-PNIPAM could just be internalized into living cells by the cell endocytosis process, thus could be selectively used for fluorescence imaging of living cells.