SPECTROFLUOROMETRIC DETERMINATION OF SUPEROXIDE ANION RADICALS AND SUPEROXIDE DISMUTASE ACTIVITY USING A 2-(2-THIENYL)BENZOTHIAZOLINE PROBE

A new fluorescent probe, 2-(2-thienyl)benzothiazoline was synthesized. Its structure was characterized with elemental analysis, IR and H-1 NMR. The fluorescent probe can be oxidized by O-2(center dot-) to form a less fluorescent product. Based on this reaction, a spectrofluorometric method was developed to determine the content of superoxide anion radicals and superoxide dismutase activity. There was a good linear relationship with a correlation coefficient 0.9996 between the scavenging percentage of O-2(center dot-) and SOD activity. The method was simple, selective, and sensitive. It was successfully applied to the determination of SOD activity in garlic and onion samples.