通过化学还原法合成了球形银纳米颗粒(Ag NPs),用电镜对其形貌进行了表征;利用紫外可见吸收光谱法、荧光光谱法以及扫描电镜研究了其与人血清白蛋白(HSA)的结合作用。随着其浓度的增加,混合溶液的紫外吸收峰强度增加,但荧光强度则发生了明显的猝灭。光谱学实验结果表明,Ag NPs与HSA在溶液中发生了相互作用,此结果也通过扫描电镜实验得到了验证。由荧光实验还可获得Ag NPs与HSA相互作用的结合常数、结合位点数以及吉布斯自由能变,由这些热力学数据可知Ag NPs与HSA可以自发结合,并成缔合物。
Ag nanoparticles (Ag NPs) were synthesized by the chemical reduction method and the morphology of them was observed by using SEM and TEM. Interaction of the Ag NPs with human serum albumin (HSA) in aqueous solution had been investigated by UV-Vis absorption spectroscopy, fluorescence (FL) spectroscopy and SEM. The absorbance of the mixture solution was progressively increased, but the fluorescence intensity was decreased with increasing concentration of Ag NPs. The results showed that there were interaction between the Ag NPs and HSA. Furthermore, the morphology change of the Ag NPs in the mixed solution investigated by SEM was in coinciding with that by UV-Vis and FL experiments. The association equilibrium constant (K), the number of binding sites (n) and the standard free energy change (△G0) were calculated by using the Stern-Volmer method. These thermodynamic data indicated that the binding processes of Ag NPs and HSA are spontaneous, and the association complex can be formed in the solution.