采用光谱法研究了Fe3+/Fe2+离子对CS-Fe3O4@ZnS∶Mn/ZnS磁性荧光复合纳米粒子(MFNPs)与牛血清白蛋白(BSA)相互作用的影响.研究结果表明, CS-Fe3O4@ZnS∶Mn/ZnS MFNPs对BSA具有荧光猝灭作用, 在有Fe3+/Fe2+离子存在时, 猝灭作用进一步加强.对猝灭曲线进行分析, 确定Fe3+/Fe2+离子对CS-Fe3O4@ZnS∶Mn/ZnS MFNPs 的猝灭为生成复合物引起的静态猝灭, 对BSA的猝灭是由碰撞引起的动态猝灭, 在有Fe3+/Fe2+离子存在时, 一方面, CS-Fe3O4@ZnS∶Mn/ZnS MFNPs通过静电作用与BSA结合形成CS-Fe3O4@ZnS∶Mn/ZnS MFNPs-BSA复合物, BSA分子结构发生改变, BSA荧光强度降低; 另一方面, Fe3+/Fe2+离子以动态猝灭的方式作用于BSA, Fe3+/Fe2+离子与CS-Fe3O4@ZnS∶Mn/ZnS MFNPs共同作用于 BSA, BSA分子结构遭到进一步破坏, 荧光猝灭更剧烈.紫外辐射条件下, 相互作用进一步加强.

The effects of Fe3+ or Fe2+ ions on the interaction of CS-Fe3O4@ZnS∶Mn/ZnS Magnetic-Fluorescent Nanoparticles(MFNPs) with Bovine Serum Albumin(BSA) have been studied using UV-visible and fluorescence spectroscopy. It was found that both the fluorescence intensity of CS-Fe3O4@ZnS∶Mn/ZnS MFNPs and BSA became weakened when Fe3+ or Fe2+ concentrations reached their physiological levels. Meanwhile, the interaction of CS-Fe3O4@ZnS∶Mn/ZnS MFNPs with BSA in the presence of Fe3+ or Fe2+ enhanced. There is synergic effect of CS-Fe3O4@ZnS∶Mn/ZnS MFNPs and Fe3+ or Fe2+ on the damage of BSA. These results are important for understanding the influence of different biological environments on interaction between MFNPs and proteins.