The Preparation And Properties Of Colorimetric Fluorescent Probes For Sensitive Detection Of Mercury

The excess accumulation of toxic substances such as mercury in the body is a serious threat to human health.The establishment of specific ultrasensitive analytical methods is of great significance in environmental protection and disease prevention.The color probe has a high selectivity,high sensitivity and a combination of a microscope to enable high levels of substance in the body to be carried out by providing a fast and easy method in vitro testing.Time-resolved real-time in situ imaging analysis and other advantages have been rapidly developed.Although the research of colorimetric fluorescent probe for detecting mercury has made great progress,most of the probes have the disadvantages of poor selectivity and low sensitivity which seriously limits their application.Therefore there is an urgent need to develop specific ultrasensitive colorimetric fluorescent probes for the detection of mercury.Based on the recognition mechanism of intramolecular charge transfer,a series of novel highly selective and ultrasensitive colorimetric fluorescent probes for mercury with simple structure were prepared by using the specific reaction-based recognition receptor.The main contents are as follows:A highly selective and sensitive colorimetric probe for monitoring inorganic and organic mercury was successfully prepared by employing benzothiazole-2-acetonitrile styrene as chromophore and vinyl ether as recognition receptor of mercury ion.After adding Hg²⁺and HgCH₃⁺in the probe solution,the color of the solution changed from colorless to yellow,so it could be used as a naked eye indicator for mercury species.In addition,the quantitative detection of mercury ions by ultraviolet visible absorption spectrometry can be used to detect the mercury ions of 2to 13nM.Based on the strong affinity of sulfur to mercury,a highly selective near-infrared fluorescence probe for mercury ion was successfully designed and synthesized by adopting thiocarbonate as recognition receptor and hydroxyl Nile red as near-infrared fluorophore.The experimental results demonstrated that this probe could detect mercury ions in the range of0⁶n M.In view of the characteristics of the near infrared emission of the probe,it is expected to be used for the in-situ analysis of mercury ions in vivo.Based on the specific reaction of mercury,we use vinyl ether as recognition receptor,4-hydroxyl-1,8-naphthalimide as fluorophore,and construct a highly selective ratiometric fluorescent probe for detecting mercury.Upon the addition of mercury ions,the probe exhibited the large red-shift?96 nm?in the fluorescence spectra.Additionally,the probe could quantitatively detect mercury ions in the range of 0 to 2.5?M with the detection limit of 0.03?M.It is important that the application of the real sample further indicated that it could provide a new method for the determination of mercury ions.This study not only provides a series of new analytical methods for the specific and sensitive detection of mercury species,but also lays the foundation for the establishment of other toxic species.