Department of Chemistry, Seoul National University, Seoul 151-747, Korea.
ACS Nano. 2013 Mar 26;7(3):2221-30. doi: 10.1021/nn305250p. Epub 2013 Mar 5.
Reactive oxygen and nitrogen species (ROS and RNS) are continuously produced in the cellular systems and are controlled by several antioxidant mechanisms. Here, we developed a straightforward, sensitive, and quantitative assay for the colorimetric and spectroscopic detection of various ROS and RNS such as H2O2, ·OH, (-)OCl, NO·, and O2(-) using glutathione-modified gold nanoparticles (GSH-AuNPs). A basic principle here is that the GSHs on the AuNP surface can be readily detached via the formation of glutathione disulfides upon the addition of ROS and RNS, and destabilized particles can aggregate to generate the plasmonic couplings between plasmonic AuNPs that trigger the red shift in UV-vis spectrum and solution color change. For nonradical species such as H2O2, this process can be more efficiently achieved by converting them into radical species via the Fenton reaction. Using this strategy, we were able to rapidly and quantitatively distinguish among cancerous and normal cells based on ROS and RNS production.
活性氧和氮物种（ROS 和 RNS）在细胞系统中持续产生，并受几种抗氧化机制的控制。在这里，我们开发了一种简单、灵敏、定量的比色和光谱测定法，用于检测各种 ROS 和 RNS，如 H2O2、·OH、(-)OCl、NO·和 O2(-)，使用谷胱甘肽修饰的金纳米粒子（GSH-AuNPs）。其基本原理是，AuNP 表面上的 GSHs 可以很容易地通过 ROS 和 RNS 的加入形成谷胱甘肽二硫化物而脱离，不稳定的颗粒可以聚集在一起，产生等离子体 AuNPs 之间的等离子体耦合，从而触发 UV-vis 光谱和溶液颜色变化的红移。对于非自由基物种，如 H2O2，通过芬顿反应将其转化为自由基物种，可以更有效地实现这一过程。使用这种策略，我们能够基于 ROS 和 RNS 的产生快速、定量地区分癌细胞和正常细胞。
