A colorimetric fluorescent probe for rapid and specific detection of nitrite

The method of fluorescent probes has been an important technique for detection of nitrite (NO2-). As an important inorganic salt, excessive nitrite would threaten humans and the environment. In this paper, a colorimetric fluorescent probe P-N (1,2-diaminoanthraquinone) with rapid response and high selectivity, which could detect NO2- by visual colour changes and fluorescence spectroscopy is presented. The probe P-N solution (pH 1) changed from pink to colourless with the addition of NO2- and fluorescence intensity at 639 nm clearly decreased. Good linear exists between fluorescence intensities and NO2- concentrations for the range 0-16 mu M, and the detection limit was 54 nM (based on a 3 sigma/slope). Moreover, probe P-N could also detect NO2- in real water samples, and results were all satisfactory. Probe P-N shows great practical application value for detecting NO2- in the environment.