芘和蒽作为荧光探针探测树枝形聚合物微环境

分别以芘和(9-蒽基)甲基三甲基溴化铵(An)作为荧光探针研究了一系列羧基为外围末端基团的芳醚树枝形聚合物Gn(n=1-4)的内部微环境极性及包结情况. 芘荧光I1/I3值在1-3代树枝形聚合物钾盐水溶液中变化不大, 而3到4代有一个陡降, 推测1-3代树枝形聚合物处于相对开放的结构, G4为相对密闭的球形结构, 4代树枝形聚合物表现出更好的包结特性. An在树枝形聚合物G2钾盐水溶液中的荧光光谱结果表明, 树枝形聚合物G2可以包结两个以上的An分子, An分子疏水的蒽环部分位于树枝形聚合物内部孔穴中, 而带正电荷的铵离子靠近树枝形聚合物分子的极性末端.

Microenvironment of Dendrimers Probing by Pyrene and Anthracene as Fluorescence Probes

The microenvironment of carboxylic acid terminated dendrimers (Gn, n=1-4) was studied by using pyrene and anthracene as probes. The results of fluorescence spectra of pyrene indicated that dendrimers G1-G3 adopted an open structure, and G4 took a more close spherical shape which showed better encapsulation capability. The results of fluorescence spectra of (9-anthrymethyl) trimethylammonium(An) in G2 potassiumaqueous solution indicated that G2 could encapsulate more than two An molecules, and the hydrophobic anthracene moiety and the hydrophilic cation portion of An encapsulated within G2 were located in the interior and the periphery of the dendrimer, respectively.