Dual signaling of Hg2+ ions by selective cleavage of thiophosphinated rhodol

Abstract

Anew Hg2+-selective reaction-based probe based on thiophosphinated N,N-diethylrhodol was developed. Thiophosphinated rhodol showed prominent chromogenic and fluorogenic signaling for the Hg2+ ions. Signaling is due to the Hg2+-assisted hydrolysis of the thiophosphinated group to generate the rhodol fluorophore. An optical signaling with a detection limit of 13 nM, detectable with unaided eyes, was realized in a mixed aqueous environment. Selective Hg2+ signaling by thiophosphinated rhodol was not significantly affected by the presence of background common metal ions. Signaling was completed within 3 min and constant under the measuring conditions between pH 6.2 and 8.0. The Hg2+ signaling based on hydrolysis of the thiophosphinated rhodol was confirmed by H-1, C-13, and P-31 NMR spectroscopy. Application of the designed probe to practical samples of tap water and wastewater was also tested. (C) 2013 Elsevier B.V. All rights reserved.