The Study Of Fluorescence And Nuclear Magnetic Resonance Imaging Probes For Detection Of Mercury Ions

Mercury is one of the strongest toxic heavy metals in our environment. Recently, the rapid development of our economy and consumption of our energy and resources cause some mercury pollution problems or potential problems. They also cause great damage to our life and production environment and bring huge health crisis to our human. The United States Environmental Protection Agency (EPA) has mandated an upper limit of2ppb (10nM) for Hg(Ⅱ) in drinking water. In order to effectively detection of mercuric content, scientists are trying to find effective detection methods. In this article, according to the previous work, we designed two probes which has significant effect for the detection of mercury ions using the character of Hg2+:1. Fluorescent probe:Because of its high fluorescence quantum yield, high selectivity, high sensitivity, real-time detection and very low detection limitation, fluorescent probes are used as ideal measuring tools for the detection of mercury ions recently. In this article, according the previous work of our group, we designed and synthesized a fluorescent probe based on the FRET theory, containing Rhodamin and Coumarin, for mercury ions. Furthermore, we used UV-absorption spectra and fluorescence emission spectra methods to do detailed test on the probe’s detection effect. We found that this probe has good selectivity and sensitivity for the detection of Hg2+. When we added the solution of Hg2+, the color of our fluorescent probe solution changed from yellow to red. This compound could form1:2complex with Hg2+. And the limited detection was1ppm.2.Dual-functional probe:Everything has two sides. Fluorescence probe has many advantages. But fluorescence probe can’t provide three-dimensional imaging owing to its poor penetrability. In this respect, nuclear magnetic resonance imaging (NMRI) technology can overcome this shortage. In this article, we introduced NMRI technology into fluorescence probe to design and synthesis a dual-functional probe based on naphthalene imide. Then we realized the dual-fuctional test for the detection of mercury ion. According to fluorescence emmision spectra and UV-absorption spectra, we found that this probe has very high selectivity for the detection of Hg2+. And the limited detection was20ppb. Though the NMRI detection of this probe, we found that the relaxivity of our probe (0.2mM in water) has linear relationship with the content of mercury ions. And this probe has been used in the imaging of laboratory rats. This work provides a basis for the dual modes, even multi-modes of molecular probes.