首先利用一种阳离子型聚电解质(多聚赖氨酸)修饰玻璃基底,并与阴离子型聚电解质(生物素化透明质酸)在静电引力下自组装,然后以生物素化透明质酸和链霉亲合素化量子点为材料,通过生物素和链霉亲合素之间的特异性结合力,层层自组装法制备了量子点一、二、三层膜。用紫外可见吸收光谱和荧光光谱对其光学性质进行表征;原子力显微镜成像表明三种膜表面均一、平整,每层的量子点都分散均匀,没有严重的聚集情况。
The formation of a new kind of biocompatible film (three layers) based on Hyaluronan biotin sodium salt (bHA) and streptavidin -quantum dots (sa-QDs) by alternate deposition of bHA and sa-QDs was investigated, atomic force microscopy, UV-Vis absorption spectroscopy, fluorescence spectroscopy were used to analyze the different aspects of the buildup process such as spectrums after a new sa-QDs adsorption, the overall surface charge of the film, and its morphology. The experiments revealed the surface of films is very uniform, when numbers of the layer is increased, the UV-Vis spectrum and fluorescence spectrum increase, and the fluorescence wavelength is blue-shift. All of the datum proved bioconjugation between two layers of the films is fine, and dispersal of the QDs in the films is good, at least not very serious aggregated.