A highly selective and sensitive photoswitchable fluorescent probe for Hg~(~(2+)) based on bisthienylethene-rhodamine 6G dyad and for live cells imaging

摘要

A new photochromic diarylethene derivative bearing rhodamine 6G dimmer as a fluorescent molecular probe is designed and synthesized successfully. All the compounds are characterized by nuclear magnetic resonance and mass spectrometry. The bisthienylethene-rhodamine 6G dyad exhibit excellent phtochromism with reversibly color and fluorescence changes alternating irradiation with ultraviolet and visible light. Upon addition of Hg~(~(2+)), its color changes from colorless to red and its fluorescence is remarkably enhanced. Whereas other ions including K~+, Na~+, Ca~(~(2+)), Mg~(~(2+)), Fe~(~(2+)), Co~(~(2+)), Ni~(~(2+)), Cu~(~(2+)), Zn~(~(2+)), Mn~(~(2+)), Pb~(~(2+)), Ni~(~(2+)), Fe~(3+), Al~(3+), Cr~(3+) and so on induce basically no spectral changes, which constitute a highly selective and sensitive photoswitchable fluorescent probe toward Hg~(~(2+)). Furthermore, by means of laser confocal scanning microscopy experiments, it is demonstrated that this probe can be applied for live cell imaging and monitoring Hg~(~(2+)) in living lung cancer cells with satisfying results, which shows its value of potential application in environmental and biological systems.