RESUMO
An improvement of chemiluminescent system for determination of peroxynitrite anion (ONOO－) has been made. In this system, the effect of some antioxidants for scavenging ONOO－ was tested. The constitute of this system and the program of starting were followed as: The ozone (O3) was bubbled through a glass-frit into 10 ml 0.01 mol/L solution of sodium azide in CB(pH 10.5) to generate ONOO－. The 800 μl ozonized solution of azide was injected into a glass tude in situ which contains 100 μl sample and 100 μl luminol solutions to initiate chemiluminescence (CL). The pluses / 6 seconds (CP6S) were determined immediately and continually for 10～30 times. A certain CL intensity (CP6S) was chosen as evaluation index to compare the activity of antioxidants. This chemiluminescent system is sensible, simple and stable. The determination limit was 8.74 μmol/L ONOO－. The linear rang was 8.74～74.04 μmol/L ONOO－. The intra batch and inter batch variation coefficient (CV%) of the analysis were 3.35%(n=10) and 5.52%(n=10) respectively. It was tested that Vit.C, teapolyphenol, procyanidin and thiourea all have effects on scavenging ONOO－.