Fluorescent Probe for Recognizing Fe3+ in Aqueous Solutions and its Applications.

This paper reports the development of a fluorescent probe (LD) for selective detection of Fe3+ in aqueous solution. LD exhibits fluorescence quenching responses toward Fe3+ with a quenching efficiency of 95%, achieving a detection limit as low as 0.70 μM. Notably, its recognition performance remains unaffected by interference from other metal ions. LD forms a 1:1 complex with Fe3+, triggering fluorescence quenching via a photoinduced electron transfer (PET) mechanism. LD-loaded test strips and medical cotton swabs enable naked-eye visual detection of Fe3+, with colorimetric changes from orange to colorless under UV light. The probe maintains selectivity within the physiological pH range, allowing its application in HeLa cell imaging.