Hg2+-selective fluorogenic signaling probe based on the hydrolysis of hydrazone

Abstract

A simple Hg2+-selective fluorogenic signaling probe based on methoxynaphthalene hydrazone was investigated. Hydrazone 1 gave prominent fluorescent signals in response to Hg2+ ions in a 1:1 mixture of acetate buffer (pH 4.8) and DMSO. The fluorescence signaling was due to the Hg2+-selective hydrolysis of hydrazone to afford the strongly fluorescent methoxynaphthaldehyde. Hg2+-selective signaling of 1 was not affected by the presence of representative metal ions as the background. Hg2+-selective fluorescence signaling by 1 was possible with a detection limit of 6.0×10−6M. As a practical application, convenient detection of Hg2+ ions using a smartphone as a portable signaling processor was conducted.