Fiber optic sensor based on fluorescence quenching for heavy metal detection

In this paper, we present the preliminary results of a fiber optic sensor based on fluorescence quenching induced by mercury (Hg) concentrations presence in aqueous solutions. The fabrication of the sensor head consists of a methyl red coating over multimode fiber tip using thermoplastic polyurethane to immobilize the thin layer. The sensor device was tested in a Hg molar concentration ranges 10-10,000 nmol/L. The experimental results show a linear dependence of the induced fluorescence quenching related to the Hg molar concentration.