A sensitive and selective method for the colorimetric detection of arsenic (As^III) ions has been demonstrated using glutathione functionalized gold nanoparticles (GSH-AuNPs). When arsenic ions are added to the GSH-AuNPs solution, the binding of arsenic ions with GSH ligands induces the aggregation of AuNPs, resulting in a rapid color change of the solution. With the implementation of a home-developed RGB extracting software, excellent linear correlation has been established between the calculated RGB color values and the arsenic concentrations (R² = 0.99488). The limit of detection (LOD) of arsenic ions is as low as 0.12 ppb. More significantly, the GSH-AuNPs solution shows excellent detection selectivity to other metal ions (Fe³⁺, Co²⁺, Ni²⁺, K⁺, Na⁺, Mg²⁺, Ca²⁺, Cu²⁺, Hg²⁺, and Pb²⁺). This method could be applied to on-site and real-time fast detection of low level arsenic ions.

使用谷胱甘肽功能化的金纳米颗粒（GSH-AuNPs）已证明了一种灵敏且选择性的比色检测砷（As ^III）离子的方法。当将砷离子添加到GSH-AuNPs溶液中时，砷离子与GSH配体的结合会诱导AuNPs聚集，从而导致溶液颜色快速变化。通过使用 自行开发的RGB提取软件，已在计算出的RGB颜色值和砷浓度之间建立了极好的线性相关性（R ² = 0.99488）。砷离子的检出限（LOD）低至0.12 ppb。更重要的是，GSH-AuNPs溶液对其他金属离子（Fe ³⁺，Co²⁺，Ni 2 ⁺，K ⁺，Na ⁺，Mg 2 ⁺，Ca 2 ⁺，Cu 2 ⁺，Hg ²⁺和Pb ²⁺）。该方法可用于现场和实时快速检测低水平砷离子。