合成了一种含邻苯二胺的偶氮染料,同时邻苯二胺在氧气存在条件下与一氧化氮(NO)反应生成苯并三氮唑结构,可很好地吸附在纳米银的表面,产生强表面增强拉曼光谱(SERS),实现溶液中NO的检测.实验中考察了染料浓度、纳米银溶胶团聚和溶液pH值等因素的影响.实验结果表明,随着NO的加入,体系的SERS信号在1200~1700nm之间发生了明显的变化,其中在1300nm左右新出现一个很强的峰.该方法检测灵敏度可达到10^-8mol/L,且适应的pH值范围在4.5~7.5之间,符合生理环境要求.
A novel diamino-azobenzene dye was designed and synthesized as a Raman indicator for NO. The Raman chemical transformation of the diamino-azobenzene structure is based on the reactivity of diamines with NO in the presence of dioxygen. The N-nitrosation of the diamino-azobenzene, yielding the benzotriazole-based compounds which exhibit a strong propensity to bind to Ag nanoparticles, offers a simple protocol for the direct detection of NO. As the addition of NO, the SERS spectra of the system changed evidently in the range of 1200-1700 nm and turned out a strong SERS peak at 1300 nm. The effects of the concentration of the dye, the aggregation of the nanoparticles and the pH of the solution were evaluated in detail. The result shows that the detection limit of the SERS probe reaches 10^-8 mol/L and the system is independent of pH in the range of 4.5-7.5.