Research Of Several Small Molecules Fluorescent Probes Based On Acylhydrazone Derivatives

In recent years, the optical probe currently drew more and more attention of chemical workers owing to the virtue of high selectivity and sensitivity, short response time, low detection limit, low-cost and easy operation, etc. It has been widely applied in the detection of various metal ions and anions. This work mainly use conjugate aromatic groups as fluorophore, nitrogen and hydroxyl oxygen atoms as complexation atoms. The several fluorescent probes of metal ions and anions have been synthesized successfully through condensation reaction. And we respectively investigated the spectral response behaviors of the probes to metallic ions. The main research results description as follows:1. A new series of simple molecule fluorescent probes M1~M6 have high selectivity to Al3+, were synthesized successfully by one-step reaction between acylhydrazine and salicylaldehyde. Dramtic enhencement on fluorescence spectra can be detected with the addition of Al3+ to the ethanol solution of M1. Optical properties of M1~M6 were hardly affected by the addition of other common background anions under the same condition. The detection limit of Al3+ reaches ~ 50 n M by M1. And the reaction mechanism of between M1 and Al3+ was investigated by 1H NMR titrations experiments.2. A Schiff base fluorescent probe M7 was synthesized through condensation reaction between 2-phenyl-2H-1,2,3-triazole-4-carboxaldehyde and salicylhydrazide. M7 was found as a fluorescent chemosensor for the detection of Al3+ in ethanol. Highly selective “turn-on” fluorescence alterations of M7 were observed upon the addition of Al3+. The detection limit of Hg2+ and Ag+ reaches ~ 12 n M by M7 and the presence of background metal ions brought very slight interference for the detection of Al3+. 1H NMR titrations experiments were performed to explain the plausible mechanism of the probing.3. A new Schiff base fluorescent probe M8 has been synthesized as a fluorescent chemosensor for Hg2+. The addition of Hg2+ to M8 solution induced a fluorescent quenching, while no obvious change could be observed in presence of other common ions. Results of competition experiments indicated recoganization of M8 to Hg2+ could not be interrupted by other metal ions. Detection limit for Hg2+ was calcuated to ~ 30 nM.