반응 기반 수은 이온 이광자 형광 프로브에 관한 연구

Abstract

Mercury(II) ions are highly toxic to living species. Owing to improper disposal of consumer products containing mercury, they are widely distributed in our environment. Human exposure to mercury species occurs largely through the consumption of contaminated fish. Therefore, the detection and monitoring of mercury species in living species are of keen concern. Otherwise various detection methods are available, the monitoring of mercury species in living species has remained as an unexplored area owing to lack of suitable probes. A promising tool for that purpose is two-photon microscopy (TPM). TPM employs two near-infrared photons for excitation and offers a number of advantages over one-photon microscopy (OPM), including increased penetration depth (greater than 500 μm), localized excitation, and prolonged observation time. The extra penetration depth that TPM affords is of particular interest in tissue imaging, because surface preparation artifacts such as damaged cells extend over 70 μm into the tissue interior. I have synthesized the two-photon probes. The new probes are coumarin and imino-coumarin precursors containing vinyl ether moiety. Upon interaction with mercury species, the vinyl ether moiety undergoes the oxymercuration reaction followed by hydrolysis, generating highly fluorescent coumarin and imino-coumarin derivatives that show two-photon absorbing property. One of the coumarin precursors senses only mercury ions among various metal cations in a fluorescence turn-on mode, whereas the other one behaves as similar ratiometic probe showing separate excitation wavelength.