Au@PVP核壳纳米粒子作为表面增强拉曼散射基底检测孔雀石绿

采用水热法合成了粒径均一、壳层厚度可控的Au@PVP核壳纳米粒子,利用壳层PVP分子分散纳米粒子的特性,使其形成均一、排列致密的单层结构,利用其内核金纳米粒子的等离子共振效应实现了孔雀石绿( MG)分子的表面增强拉曼检测。通过优化吸附时间与壳层厚度,在致密的、均匀的核壳纳米粒子表面增强拉曼散射(SERS)基底上实现MG分子高灵敏分析检测,检测线性范围1×10-10~1×10-5 mol/L,线性相关系数R2达到0.98,检出限可达1×10-12 mol/L。将本方法用于罗非鱼鱼肉中MG含量检测,样品未检出,样品加标回收率为70.8％~126.0％。结果表明,本方法快速准确、操作简单,可用于鱼肉中MG的快速检测。

Au@PVP Core-Shell Nanoparticles Used as Surface-Enhanced Raman Spectroscopic Substrate to Detect Malachite Green

The core-shell nanopaticles of Au@polyvinyl-pyrrolidone ( PVP) with uniform size and controllabe shell-thickness were prepared by hydrothermal method. The core-shell nanoparticles could be assembled to be the monolayer array on Si substrate relying on the dispersion of core-shell nanoparticles arising from PVP shell. The malachite green ( MG ) absorbed by H-bond could be detected on the array under the electromagnetic enhancement of inner-core Au nanoparticles. Under the conditions of the optimum shell-thickness of Au@PVP and the appropriate absorbed time of MG, the detection of MG could be realized in the linear range from 1 × 10-10 mol/L to 1 × 10-5 mol/L with the correlation coefficient ( R2 ) of 0. 98. The detection limit was 10-12 mol/L. This method was applied to the determination of MG in tilapia fish fillets of Xiagang market. No MG was found in this real sample. The spiked recoveries of the sample ranged from 70. 8% to 126. 0%. This method is simple and accurate, and can be used for detection of MG in the fish.