A novel Fe3+ fluorescent probe based on rhodamine derivatives and its application in biological imaging

• A Fe 3+ -specific probe based on rhodamine B was designed and synthesized. • It can achieve the effect of naked eye detection through color change. • The probe has low detection limits and high binding constants. • The probe can be used to detect Fe 3+ in Hela cells and zebrafish. In this paper, rhodamine B was used as the fluorophore to design and synthesize a probe RBPH for Fe 3+ detection. The properties of the probe RBPH were investigated by UV-Vis absorption spectroscopy and fluorescence emission spectroscopy. The results showed that the probe had a detection limit of 75.9 nM and a binding constant of 0.608 × 10 4 M −1 . Compared with the published rhodamine B class Fe 3+ probes, the probe RBPH has the advantage of rapid response. Biological experiments show that the probe has good biocompatibility, low toxicity and good cell penetration ability. The probe RBPH can be successfully applied to the determination of Fe 3+ ions in Hela cells and zebrafish, and a good fluorescence imaging effect can be seen by laser confocal microscopy.