A novel colorimetric chemosensor for Cu2+ with high selectivity and sensitivity based on Rhodamine B

摘要

9-formyl-8-hydroxy-2,3,6,7-tetrahydro-1H, 5H-benzo[ij]-quinolizine rhodamine B hydrazone (FHQRH), a novel colorimetric chemosensor for Cu2+, was synthesized by a three-step synthetic route. It was found that FHQRH showed a high selectivity for Cu2+ ions and excellent anti-interference capability toward other metal ions. The FHQRH solution exhibited a visual color change after the addition of Cu2+, owing to the open spirocyclic structure via coordination with Cu2+. The complexation coefficient of FHQRH toward Cu2+ was measured to be 1:1. Furthermore, this Cu2+ chemosensor has a remarkable low detection limit of 0.45 mu M, which is 2 % of the toxic level (20 mu M) in drinking water as defined by the US Environment Protection Agency (EPA).