CdTe nanocrystals-enhanced chemiluminescence from peroxynitrous acid-carbonate and its application to the direct determination of nitrite

It was found that CdTe semiconductor nanocrystals (NCs) can induce a great sensitized effect on chemiluminescence (CL) emission from peroxynitrous acid (ONOOH)-Na2CO3 system. CL spectra, fluorescence (FL) spectra, and the quenching effect of reactive oxygen species were used to investigate the CL reaction mechanism. The CL intensity was proportional to the concentration of nitrite in the range from 0.05 to 50 mu M. The detection limit (S/N = 3) was 0.024 mu M and the relative standard deviation (RSD) for five repeated measurements of 0.5 mu M nitrite was 4.2%. This method has been successfully applied to determine nitrite in well water samples with recoveries of 94.0-100.5%. This was the first work for direct (not inhibition effect) determination of analytes using semiconductor NCs-based CL sensor. (C), 2011 Elsevier B.V. All rights reserved.