气/液界面自组装金纳米粒子薄膜作为SERS基底检测三聚氰胺

采用气/液界面自组装方法制备金纳米粒子薄膜作为SERS基底,其结构规整、均匀,利用此基底对三聚氰胺实现高灵敏的半定量分析。此SERS基底的制备是直接于水相合成的金纳米粒子中加人正十二硫醇,金纳米粒子通过硫醇修饰后由亲水性转变成疏水性质,在相界面上自组装为致密金纳米粒子单层膜结构。这种SERS基底不仅制备方法简单,而且应用范围广,除了检测三聚氰胺还可以拓展到其他的非极性的分子如多环芳烃等高灵敏的半定量分析。

Self-Assembled Film of Gold Nanoparticles at a Air/Water Interface Used as a SERS Substrate to Detect Melamine

Self-assembled monolayer film of gold nanoparticles(55 nm) was formed at air-water interface by the driving force of wettability-shift of gold nanoparticles from hydrophilic property to hydrophobic property when encapsulated with 1-dodecanethiol.SEM image shows that the structure of the surface is nearly monolayer with closed arrays of uniform particle size when the film is transferred onto Si wafer.The substrate can be used for SERS substrate to realize semiquantitative analysis of melamine and the detection limit can reach 1×10-9 g·L-1.This SERS substrate is of wide application,not only for melamine but also for nonpolar molecule such as polycyclic aromatic hydrocarbons.