Electrochemical biosensors as a tool for antioxidant capacity assessment

Oxidative stress arises from the excess of free radicals due to environmental or behavioural stressors, or simply to a malfunction of the antioxidant production. It produces damage to lipids, proteins or DNA, impeding normal cell functioning and leading to numerous human diseases, as well as to the aging process. Antioxidants respond to this problem, scavenging the free radicals. This article critically reviews the electrochemical biosensors developed for the evaluation of the antioxidant capacity of specific compounds. Three different sensing approaches are described, based on cytochrome c, superoxide dismutase and DNA. Due to the ability of these devices to perform simple, fast and reliable analysis, they are promising biotools for the assessment of antioxidant properties. (C) 2001 Elsevier B.V. All rights reserved.