羊毛角蛋白保护金纳米簇的制备及表征

Preparation and Characterization of Wool Keratin-Protected Gold Nanoclusters

利用羊毛角蛋白作为还原剂,制备了具有高荧光性能的金纳米簇。采用荧光光谱仪、紫外-可见吸收光谱仪、傅里叶变换红外光谱仪及透射电子显微镜对试样的结构与性能进行了表征。结果表明,羊毛角蛋白中的巯基在合成金纳米簇的过程中起着关键作用。巯基含量越多,所得到的金纳米簇的荧光强度越高,其中高硫角蛋白合成的金纳米簇(WK_2@AuNCs)的荧光强度是低硫角蛋白合成的金纳米簇(WK_1@AuNCs)的3倍,且前者的粒径要大于后者。分析二级结构含量可知,α-螺旋结构的减少和β-折叠结构的增加是导致荧光强度增加的主要原因。

Gold nanoclusters with high fluorescence intensity were synthesized with wool keratin as reducing agents.The structure and characterization of wool keratin-protected AuNCs(WK@AuNCs)specimens were investigated by fluorescence spectroscopy,UV-vis absorption spectroscopy,Fourier transform infrared spectroscopy and transmission electron microscopy.The results show that thiol groups of wool keratin play an important role in the preparation of gold nanoclusters.The more thiol groups,the higher fluorescence intensity.The fluorescence intensity of the WK2@AuNCs synthesized by high thiol groups is three times as the WK1@AuNCs synthesized by low thiol groups.Furthermore,the particle diameter of WK2@AuNCs is larger than that of WK1@AuNCs.Based on the analysis of the content of second structures of WK@AuNCs,it is evident that the main effect on fluorescence intensity is due to the decrease ofα-helices and the increase ofβ-sheets.