Fluorescence and Surface Enhanced Raman Scattering Dual Modal Detection of Zn2+ Based on Complexation Reaction-Induced Self-Aggregation of Nanoparticles
纳米光学探针具有独特的结构特征和光学特性，受到广泛的关注。本研究合成了一种新的荧光/表面增强拉曼散射（SERS）双模式纳米光学探针，利用羟基苯甲酸衍生物（NAMH）的酚羟基和席夫碱对Zn2+具有优良亲和力的特性，构建了NAMH修饰银纳米颗粒（AgNPs@NAMH）探针，AgNPs@NAMH与Zn2+之间发生特异的络合作用，诱导荧光信号猝灭，可用于复杂样本中Zn2+的荧光检测，检出限为0.32 nmol/L。此外，络合反应引发AgNPs发生自聚集，可实现对Zn2+的超灵敏SERS检测，检出限为0.68 pmol/L。本方法具有操作简单、快速、高灵敏和高选择性等优点，为环境污染物的即时检测提供了技术支持。
Optical nanoprobes have attracted extensive attention in area of analytical chemistry because of their unique structural characteristics and optical properties. In this study, a novel fluorescence/surface-enhanced Raman scattering (SERS) dual-modal nanoprobe was developed. The phenolic hydroxyl group and Schiff base of hydroxybenzoic acid derivative (NAMH) exhibited a preferential affinity towards Zn2+. The complexation between AgNPs@NAMH and Zn2+ induced the quenching of the fluorescent signal of NAMH, thus enabling the fluorescent detection of Zn2+ in complex samples with a detection limit of 0.32 nmol/L. Moreover, the Zn2+-triggered AgNPs aggregation led to the formation of abundant “hot spots” among NPs, which could be used for SERS analysis of Zn2+ with a detection limit of 0.68 pmol/L. This method had a number of advantages over conventional approaches in simplicity of operation, rapidity, high sensitivity and high selectivity, and provided new technical support for the immediate detection of environmental pollutants.