A Highly Selective Fluorescent “Turn on” Probe for Al3+ Based on Pyrazolone

Abstract A highly selective fluorescent “turn on” probe for Al 3+ based on the conjugate of aminourea and pyrazolone was devised and synthesized. The fluorescence intensity of the probe solution was significantly enhanced by the addition of Al 3+ to the probe solution. Other cations such as Cu 2+ , Ni 2+ , Fe 3+ , Co 2+ , Ag + , Mn 2+ , Sn 2+ , Sn 4+ , Mg 2+ , Li + , Zn 2+ , Zr 4+ , Ce 3+ , Ca 2+ , and Na + did not interfere the detection of Al 3+ . The 1 : 1 complexation between Al 3+ and the probe was confirmed by Job's plot curve. In addition, the solution of the complex formed by Al 3+ and the probe can be used for the specific detection of Hg 2+ , appearing as fluorescence quenching.