Fluorescent determination of Hg2+ in water and fish samples using a chemodosimeter based in a Rhodamine 6G derivative and a portable fiber-optic spectrofluorimeter

• Published in: Applied spectroscopy Vol. 64; no. 5; p. 520
• Main Authors: Bohoyo Gil, Diego, Rodriguez-Cáceres, María Isabel, Hurtado-Sánchez, María del Carmen, Muñoz de la Peña, Arsenio
• Format: Journal Article
• Language: English
• Published: United States 01.05.2010
• ISSN: 1943-3530
• DOI: 10.1366/000370210791211600

A fluorimetric chemodosimeter (FC1), based on a Rhodamine 6G derivative, is proposed for the recognition of Hg(2+) ions in water and fish samples. The reagent shows a highly selective and sensitive reaction with Hg(2+), giving rise to strong fluorescence emission at 555 nm. The obvious color change of the solution from colorless to pink upon the addition of Hg(2+) demonstrates that FC1 can be used for "naked-eye" detection of Hg(2+) in water effluents. The fluorescence intensity is proportional to the amount of Hg(2+) at ng mL(-1) levels, and it is capable of distinguishing between safe and toxic levels of inorganic mercury in drinking water and fish samples. The procedure has been implemented in a portable instrument composed of a 515 nm light-emitting diode (LED) excitation source, two fiber optics, and a charge-coupled device (CCD) camera as detector, connected to a portable computer for data acquisition and analysis, intended for in situ determination of mercury, offering a viable alternative to a conventional spectrofluorimeter. The proposed method has been applied to different water and fish samples with satisfactory results.