Using organic nanoparticle fluorescence to determine nitrite in water.

Organic fluorescence nanoparticles (1-aminopyrene nanoparticles) were prepared under ultrasonic radiation and used to determine nitrite. Such nanoparticles have a broad, continuous excitation spectrum, but they are also photochemically stable and water-soluble. Nitrite determination was based upon nitrite quenching the fluorescence of the nanoparticles due to a simple diazotization reaction; a simple and specific method. Under optimal conditions, the linear range of the calibration curve was 20-1400 ng ml(-1), with a correlation coefficient of 0.9987 for nitrite. The detection limit was 3 ng ml(-1). The method was applied to various water samples from several sources. Quantitative nitrite recoveries and satisfactory results were achieved.