Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University , Lanzhou 730070, P. R. China.
Department of Chemistry, Tianjin University , Tianjin 300072, P. R. China.
Anal Chem. 2017 Mar 21;89(6):3538-3544. doi: 10.1021/acs.analchem.6b04805. Epub 2017 Feb 27.
Herein, we developed a general strategy for rapid, highly selective, and ultratrace naked-eye colorimetric detection of Hg in aqueous solutions. Two dimensional rGO/PEI/Pd nanohybrids, where rGO, PEI, and Pd were referred to as reduced graphene oxide, polyethylenimine, and Pd nanoparticles, respectively, were synthesized and used as mimetic peroxidase for selective and ultrasensitive detection of Hg in water and human serum samples. In the presence of mercury ions, the peroxidase mimetic activity of rGO/PEI/Pd nanohybrids was found to be stimulated and enhanced significantly, which promoted the effective oxidation and color change of 3,3',5,5'-tetramethylbenzidine (TMB) in solution to dark blue that was detected by the naked-eye and the absorption spectroscopic method. The proposed sensing strategy coupled with spectroscopic detection method showed an ultralow detection limit of 0.39 nM for Hg in ddHO and ∼1 nM in wastewater as well as serum samples, respectively. On the basis of the colorimetric assay, a minimum concentration of ∼10 nM for Hg in wastewater and human serum can be detected with the naked-eye. The naked-eye-based colorimetric assay for sensitive and selective detection of mercury is expected to hold huge potentials in applications such as environmental monitoring, clinical diagnosis, and pharmaceutical analysis.
在此，我们开发了一种用于快速、高选择性和痕量裸眼比色法检测水溶液中 Hg 的通用策略。二维 rGO/PEI/Pd 纳米杂化物，其中 rGO、PEI 和 Pd 分别指还原氧化石墨烯、聚乙烯亚胺和钯纳米颗粒，被合成并用作模拟过氧化物酶，用于在水和人血清样品中选择性和超灵敏地检测 Hg。在汞离子存在下，rGO/PEI/Pd 纳米杂化物的过氧化物酶模拟活性被发现得到显著刺激和增强，这促进了溶液中 3,3',5,5'-四甲基联苯胺（TMB）的有效氧化和颜色变化为深蓝色，可通过肉眼和吸收光谱法检测。所提出的传感策略与光谱检测方法相结合，分别对 ddHO 中的 Hg 显示出超低检测限为 0.39 nM，对废水和血清样品中的 Hg 分别为约 1 nM。基于比色测定法，可通过肉眼检测到废水中和人血清中 Hg 的最低浓度约为 10 nM。用于敏感和选择性检测汞的基于肉眼的比色法有望在环境监测、临床诊断和药物分析等应用中具有巨大潜力。
