作者
Jiaqi Xu,Y.M. Zhang,Xun Zhu,Guixia Ling,Peng Zhang
摘要
Heavy metal pollution poses a major threat to human health, and developing a user-deliverable heavy metal detection strategy remains a major challenge. In this work, two-mode Hg2+ sensing platforms based on the tunable cobalt metal-organic framework (Co-MOF) active site strategy are constructed, including a colorimetric, and an electrochemical assay using a personal glucose meter (PGM) as the terminal device. Specifically, thymine (T), a single, adaptable nucleotide, is chosen to replace typical T-rich DNA aptamers. The catalytic sites of Co-MOF are tuned competitively by the specific binding of T-Hg2+-T, and different signal output platforms are developed based on the different enzyme-like activities of Co-MOF. DFT calculations are utilized to analyze the interaction mechanism between T and Co-MOF with defect structure. Notably, the two-mode sensing platforms exhibit outstanding detection performance, with LOD values as low as 0.5 nM (colorimetric) and 3.69 nM (PGM), respectively, superior to recently reported nanozyme-based Hg2+ sensors. In real samples of tap water and lake water, this approach demonstrates an effective recovery rate and outstanding selectivity. Surprisingly, the method is potentially versatile and, by exchanging out T-Hg2+-T, can also detect Ag+. This simple, portable, and user-friendly Hg2+ detection approach shows plenty of promise for application in the future. Heavy metal pollution poses a serious threat to the ecological environment. Mercury ion (Hg2+), a type of heavy metal ion with high toxicity, is bio-accumulative, difficult to degrade, and has a significant affinity for proteins containing sulfur and thiol, which seriously endangers the ecological environment and human health. In this paper, two-mode Hg2+ sensor platforms based on tunable Co-MOF active sites are constructed, which are expected to achieve simple, portable, and fast multi-scene Hg2+ detection.