A new multifunctional Schiff base as a fluorescence sensor for Fe2+ and F− ions, and a colorimetric sensor for Fe3+

A multifunctional Schiff base fluorescent sensor (receptor L) was prepared and its metal ions and anions sensing properties were investigated. Receptor L exhibited an excellent selective fluorescence response toward Fe2+ and F−. It also showed colorimetric response (from colorless to yellow) toward Fe3+ among a series of ions. Moreover, the detection limits of receptor L for Fe2+ and F− were determined to be 0.3 ppm and 25.7 ppb, respectively. The two detection limit values were sufficiently low to detect nano-molar concentration of Fe2+ and F−.