Study and application of flow injection spectrofluorimetry with a fluorescent probe of 2-(2-pyridil)-benzothiazoline for superoxide anion radicals

This paper presents an automatic spectrofluorimetric method (flow injection spectrofluorimetry) using a novel fluorescent probe named H. Py. BA (2-(2-pyridil)-benzothiazoline) for determining superoxide dismutase (SOD) activity. The fluorescent probe was synthesized in house and fully characterized by elemental analysis and by infrared and H-1 nuclear magnetic resonance spectra. It could specially identify and trap O-2(-.) and was oxidized by O-2(-.) to form a strong fluorescence product. Based on this reaction, the flow injection spectrofluorimetric method was proposed and successfully used to determine SOD activity. The proposed method has a better selectivity in the determination of reactive oxygen species because the probe can be oxidized only by O-2(-.) excluding H2O2. As a kind of simple, rapid, precise, sensitive and automatic technique, it was applied to measurement of SOD activity in scallion, garlic, and onion with satisfactory results. (C) 2004 Published by Elsevier Inc.