Determination of superoxide dismutase in erythrocytes by a chemiluminescent assay

A highly rapid chemiluminescent assay for the determination of superoxide d ismutase (SOD) activity in erythrocytes was developed. The inhibition of th e luminescent emission caused by the decrease of generated superoxide anion s was measured. The aim of this work was to verify the application of a non amplified luminol SOD luminescent assay (CLM) in erythrocytes starting fro m an amplified method already used for the determination of XOD activity in milk (CLME). Both the assays had a detection limit of 3 x 10(-2) +/- 7 x 1 0(-3) U/ml of SOD at 2 sigma level, and a linear range of activity from 5.2 to 0.03 U/ml of SOD. The imprecision of assays (repeatability) presented c oefficients of variations ranging from 3.1 to 7.9% for the CLME method and from 0.6 to 17.7% for CLM method. Both luminescent techniques were compared using a spectrophotometric kit, that had a detection limit of 0.3 U/ml, an d showed good agreement. (C) 2000 Elsevier Science B.V. All rights reserved .