A Colorimetric and Fluorescent Probe Based on Rhodamine B for Detection of Fe3+ and Cu2+ Ions

Development of optical probe for the detections of Fe 3+ and Cu 2+ is one of the most active and interesting research directions in analytical chemistry because of their vital roles in the environment protection and human health. Herein, a turn on optical rhodamine B-based probe (probe 1) with the significant changes in color and fluorescence has been prepared. The color of this probe solution changed from colorless to amaranth in the presence of Fe 3+ and to pink in the presence of Cu 2+ , which is promising for the qualitative recognition of Fe 3+ and Cu 2+ . More importantly, probe 1 could be used for the quantitative analysis of Fe 3+ and Cu 2+ by fluorescence enhancement. The detection limits for Fe 3+ and Cu 2+ reached 8.1 × 10 −8  M and 4.8 × 10 −7  M, respectively. Furthermore, it was found that this probe can also be used for fluorescence imaging of Fe 3+ and Cu 2+ in living cells.