A facile flow-through phosphorimetric sensing device for simultaneous determination of naptalam and its metabolite 1-naphthylamine

This paper presents the development of a single flow-through phosphorescence optosensor for simultaneous determination of pesticide N-1-naphthylphthlamic acid (NAP) and its metabolite 1-naphthylamine (NNA). The system works as a simple and rapid phosphorimetry-biparameter sensor. It is based in the on-line immobilization of the analytes onto a non-ionic resin solid support (Amberlite XAD 7) in a continuous flow system, followed by the measurement of their native phosphorescence. The determination was performed using 0.2 M TlNO₃ and 15 mM Na₂SO₃ in a carrier flow. The developed sensor was satisfactorily applied to the determination of these pesticides in drinking and mineral waters (recovery percentages between 82.8 and 114.1% with inferior relative standard deviations to 3.1%).