Copper ion-mediated glyphosate detection with N-heterocycle based polyacetylene as a sensing platform

Two novel disubstituted polyacetylenes (TZP and PBP) with triazole and 2-(pyridin-2-y1)-1H-benzo[d]imidazole as the side groups, respectively, were successfully synthesized through using a post-functionalization strategy, and their fluorescence responses to metal ions and pesticides were investigated in detail. Strong emission from TZP and PBP could be efficiently quenched by a trace of Cu2+, through an electron or energy transfer process. The addition of Glyphosate (Glyp) to the solution of TZP/Cu2+ and PBP/Cu2+ complexes could recover the emission of TZP and PBP, and exhibit good "turn on" sensing signals for monitoring Glyp. These complex sensors had the high selectivity to Glyp without the interference from other anions and pesticides. The PBP/Cu2+ complex showed much higher sensitivity and a lower detection limit (8.0 x 10(-8) M) for Glyp than that of TZP/Cu2+ complex. With the aid of PBP/Cu2+ complex, Glyp could be differed from other pesticides visually by its strong blue emission under the hand-held UV lamp, at the concentration as low as 1.0 x 10(-5) M. This work provides a new strategy for the development of Glyp sensors. (C) 2016 Elsevier B.V. All rights reserved.