An AIE polymer prepared via aldehyde-hydrazine step polymerization and the application in Cu2+ and S2− detection

Abstract

Herein we reported the synthesis of a novel amphiphilic AIE (aggregation-induced emission) polymer with salicylaldehyde azine (SA) moieties and PEG segments in the backbone via the aldehyde-hydrazine step polymerization. The polymer can self-assemble into stable micelles in water at ambient temperature and display intense orange fluorescence because of the aggregation of SA moieties in the core. Moreover, the polymer was found to be thermoresponsive with a relatively high LCST (lower critical solution temperature) and the LCST can be tuned via the chain length of PEG segments. The polymer micelles formed at ambient temperature can serve as a turn-off fluorescent probe for the selective detection of Cu2+ in aqueous media with a low detection limit of 53 nM. The fluorescence of polymer can be completely quenched by Cu2+ and the formed polymer-Cu2+ complex can be used as a turn-on fluorescent probe for the selective detection of S2− with a detection limit of 0.24 μM. The polymer is expected as a useful fluorescent probe for the selective detection of Cu2+ and S2− in environmental field.