A novel near-infrared turn-on fluorescent probe for the detection of Fe3+ and Al3+ and its applications in living cells imaging.

Abstract

In this study, a new hemicyanidine-based colorimetric-fluorescent probe L has been synthesized and characterized by X-ray single crystal diffraction, NMR, HRMS and other technologies. The probe L serves as a "turn-on" probe for the detection of Fe3+ and Al3+ ions in DMF-HEPES system with a high sensitivity and an excellent selectivity. The probe L manifesting the color of the solution containing L turns red on the addition of Fe3+, and turns pink on the addition of Al3+. The fluorescence turn-on detection of Fe3+ and Al3+ ions is attributed to the photo-induced electron transfer (PET) process and the exertion of the chelation-enhanced fluorescence effect (CHEF) mechanism. The results of thin layer silica gel plate coloration experiments also present the same characteristics. Additionally, we further demonstrate that the probe L exhibit good cell permeability and could be employed to monitor Fe3+ and Al3+ ions in the living cells.