A porphyrin-based chemosensor for colorimetric and fluorometric detection of cadmium(II) with high selectivity

Abstract

A new chemosensor (ProE) based on a functionalized porphyrin for colorimetric and fluorometric detection of cadmium ions ( Cd 2+) was outlined. ProE displays a distinct color change, as well as dramatic ratiometric variations in absorption and fluorescent emission spectra upon exposure to Cd 2+. This condition allows the detection of the analyte at concentrations as low as 0.073 μM. The dual chromo- and fluorogenic responses of the probe are attributed to the formation of a 1:1 Cd 2+/ProE complex, which ultimately affects its optical properties. The sensor also exhibited high selectivity and sensitivity toward Cd 2+ over other common metal ions in a moderate pH range, leading to potential fabrication of both "naked-eye" and ratiometric fluorescent detection of Cd 2+.