蛋清生物模拟矿化合成荧光银纳簇和氰化物荧光探针

Synthesis of Eggwhite Protein-Based Fluorescent Silver Nanoclusters by Biomimetic Mineralization for Probing Cyanide

发展了一种合成荧光银纳簇的新方法。采用易得的生物蛋白材料蛋清,无需其他还原剂,调节pH值后,通过最简便的一锅孵化法制备了荧光银纳簇。这种合成方法类似于自然界的生物矿化现象:生物分子捕获无机离子,在功能性分子作用下进行矿化过程。高分辨透射电镜分析表明纳簇的粒径小于2 nm。该合成方法环保经济。紫外-可见吸收光谱和荧光发射光谱分析表明这种银纳簇能快速响应氰离子,导致吸光度减弱,并伴随荧光猝灭。基于此原理建立了一种检测氰离子的荧光传感新方法,此分析方法显示良好的线性范围和选择性,较高的灵敏度。检测限为1.2μmol.L-1,低于世界卫生组织推荐的饮用水标准(氰化物浓度不高于2.7μmol.L-1)。

A new synthesis strategy for fluorescent silver nanoclusters was developed.During this synthesis process,without any other reductants,only facile biomaterials,i.e.,eggwhite proteins,were used as materials and scaffolds for preparation of silver nanoclusters.By simple incubation process under the optimum conditions,this one-pot methodology yielded nanoclusters with unique optical properties.The mechanism of this synthesis strategy was presumably based on Biomimetic Mineralization： sequestering and interacting with inorganic ions,followed by providing scaffolds for minerals formed,mostly through functional proteins.The diameters of this nanoclusters were smaller than 2 nm,which charaterized by the analysis of transimission electron microscopy.Obviously,this synthesis strategy was simple,environmental friendly and cost-efficient.Additionally,a novel silver nanocluster-based fluorescent probe for cyanide in aqueous solution was described.This probe relied on the cyanide etching-mediated fluorescence quenching of the silver nanoclusters,which also was confirmed by the analysis of absorption spectra.Thus sensing assay for cyanide possesses highly sensitivity and selectivity,and good linearity.With this probe,the detection limit was down to 1.2 μmol·L-1 and lower than the maximum level（2.7 μmol·L-1） of cyanide anion in drinking water proposed by the World Health Oranization（WTO）.