A quinoline-rhodamine hybrid probe for ratiometricly sensing of Hg2+ in water and cell imaging application

To develop efficient tools for monitoring toxicant Hg2+ in aqueous solution attracts great attention because the abnormal distribution of Hg2+ in environment poses great threat to human health. We here report the preparation of a novel quinoline-rhodamine hybrid fluorescent probe P7RHg for ratiometricly sensing of Hg2+ in water, with a spirolactam-thiosemicarbazide reaction group. Upon treatment by Hg2+, the ratio of fluorescence intensity (F-600/F-460) exhibits nearly 90-fold enhancement, presenting two well-resolved emission peaks (140 nm). Meanwhile, the specific Hg2+-induced desulfurization provides probe P7RHg an excellent selectivity to Hg2+, with a detection limit of 8.6 nM. Moreover, the low cytotoxicity allows P7RHg to be employed for tracing Hg2+ in living cells by confocal fluorescence imaging.

Automated summary

In this study, a novel fluorescent probe P7RHg was developed for colorimetric sensing of Hg2+ in water. The probe showed enhanced fluorescence intensity ratio and excellent selectivity towards Hg2+ with low cytotoxicity, making it suitable for live cell imaging of Hg2+.