Automated analysis of the serum antioxidative activities against five different reactive oxygen species by sequential injection system with a chemiluminescence detector

BackgroundThere is a growing evidence that reactive oxygen species (ROS) may cause many pathologic conditions including chronic diseases, neurodegenerative disorders, cancer and aging. There are a number of methods to measure the total antioxidative activity of the serum. However, since the lifetime and oxidative activity of various types of ROS are all different, to measure simply the total antioxidative activity of the serum is not enough. Therefore, to aid the diagnosis and to improve the therapeutic strategy, it is important to develop a simple and reliable method of assaying antioxidative activity of the serum.MethodsA method that combines sequential injection analysis (SIA) and luminol chemiluminescence (CL) detection was employed for the measurement of antioxidative activities of human serum. We collected sera from healthy subjects (n = 42) and patients with diabetes (n = 39) and rheumatoid arthritis (n = 25) and tested the sensitivity, reproducibility and reliability of our method.ResultsSince the operation is automatically controlled by a personal computer, we obtained a satisfactory repeatability without the need of much manpower. The time required for obtaining the antioxidative activity against one ROS for one individual is less than 3 min. Although the value of antioxidative activity varies from subject to subject, there were a certain relationship between the disease and the antioxidative values of each type of ROS. The results suggest that the measurement of antioxidative activity against different ROS may provide us with valuable information regarding the disease state.ConclusionsThe evaluation of antioxidative activities against each ROS by the proposed method should be more informative to understand the antioxidative status of biological fluid.