National Circular Economy Engineering Laboratory, College of Chemical Engineering, Sichuan University of Science & Engineering, Zigong, 643000, P. R. China.
Mikrochim Acta. 2023 May 30;190(6):245. doi: 10.1007/s00604-023-05826-8.
A low-cost and environment-friendly sensor was developed for visual determination of gold ions (Au) by using label-free hydrogen doped molybdenum oxide (HMoO) nanoparticles as ratio probes. According to the characterization results of transmission electron microscopy, scanning electron microscopy, X-ray powder diffraction, and Fourier transform infrared spectra, Au is easily reduced to red Au nanoparticles (AuNPs) by blue HMoO nanoparticles. The color change of the solution depends on the concentration of Au, which makes it possible to detect Au visually. Under optimal experimental conditions of pH 4.6, HMoO nanoparticles concentration of 0.075 mg·mL, and reaction time of 7 min, the sensor offers a satisfactory determination range from 0.5 to 70 μM and a good determination limit of 0.45 μM for Au. The concentration of Au as low as 10 μM can be directly distinguished through the naked eye. Additionally, the colorimetric probe has also been proved applicable in environmental water samples. More importantly, the resulting AuNPs have good stability and oxidase-like activity, which may be directly used in sensing, catalysis, energy, and other fields.
一种低成本、环保的传感器，用于通过使用无标记的掺氢氧化钼（HMoO）纳米粒子作为比率探针来可视化测定金离子（Au）。根据透射电子显微镜、扫描电子显微镜、X 射线粉末衍射和傅里叶变换红外光谱的表征结果，蓝色 HMoO 纳米粒子很容易将 Au 还原为红色金纳米粒子（AuNPs）。溶液的颜色变化取决于 Au 的浓度，这使得 Au 能够进行可视化检测。在最佳实验条件下（pH 值为 4.6、HMoO 纳米粒子浓度为 0.075mg·mL-1、反应时间为 7min），该传感器提供了令人满意的测定范围为 0.5 至 70μM，Au 的检测限为 0.45μM。浓度低至 10μM 的 Au 可以通过肉眼直接区分。此外，比色探针也已被证明适用于环境水样。更重要的是，所得到的 AuNPs 具有良好的稳定性和氧化酶样活性，可直接用于传感、催化、能源等领域。
