The Use of Cyclic Voltammetry for the Evaluation of Antioxidant Capacity

Abstract

Low-molecular weight antioxidants (LMWAs) play a major role in protecting biological systems against reactive oxygen-derived species and reflect the antioxidant capacity of the system. Cyclic voltammetry (CV), shown to be convenient methodology, has been validated for quantitation of the LMWA capacity of blood plasma, tissue homogenates, and plant extracts. Analysis of the CV tracing yields the values of (i) the biological oxidation potential, E and E l/2 , which relate to the nature of the specific molecule(s); (ii) the intensity (la) of the anodic current; and (iii) the area of the anodic wave (S). Both la and S relate to the concentration of the molecule(s). LMWA components of human plasma and animal tissues were identified and further validated by reconstruction of the CV tracing and by high-performance liquid chromatography-electrochemical detection. To reflect the oxidative stress status, the use of an additional parameter, R, has been proposed. R represents the level (%) of oxidized ascorbate (compared with total ascorbate) and is measured by high-performance liquid chromatography-electrochemical detection. All these parameters were monitored in healthy human subjects as well as in chronic (diabetes mellitus) and acute care patients (subjected to total body irradiation before bone marrow transplantation). The electroanalytical methodologies presented here could be widely employed for rapid evaluation of the status of subjects (in health and disease) for monitoring of their response to treatment and/or nutritional supplementation as well as for screening of specific populations.

Troxerutin, a plant flavonoid, protects cells against oxidative stress-induced cell death through radical scavenging mechanism

“…Essentially, two parameters, namely oxidation peak position and the area under the peak were used for this purpose (Chevion, Roberts & Chevion, 2000;Zielinska, Nagels & Piskula, 2008 with Millipore water and further cleaned electrochemically, using 0.5 M H 2 SO 4 .…”

Electrochemical determination of antioxidant capacity of fruit tea infusions

“…Although cyclic voltammetry at an inert glassy carbon electrode has been successfully applied to analyse antioxidants present in wine (Kilmartin, Honglei, & Waterhouse, 2002;Piljac, Martinez, Stipčević , Petrović , & Metikoš-Huković , 2004;PiljacŽegarac, Martinez, Valek, Stipčević , & Kovačević -Ganić , 2007), fruit juices (Piljac-Žegarac, Valek, Martinez, & Belščak, 2009), plant extracts (Chevion, Chevion, Boon Chock, & Beecher, 1999), phenolic standards (Yakovleva et al, 2007), and even human plasma (Chevion, Roberts, & Chevion, 2000), there is no data available from cyclic voltammetry studies of ready-made fruit teas. Cyclic voltammetry has numerous advantages over the other mentioned methods; it is rapid, affordable and sensitive enough for determination of physiological concentrations of antioxidants.…”

Magnetic hydrotalcites as solid basic catalysts for cellulose hydrolysis

“…So, the half-wave reduction potentials (E 1/2 ) of the samples were 0.172 V for the LDH-3, 0.189 V for the LDH-2 and 0.191 V for the LDH-4. E 1/2 reflects the specific reducing power of a component, which is in accord with the oxidizability (Chevion et al, 2000;Tonzola et al, 2003). The LDH-3, the lowest oxidation potential, demonstrated the strongest ability to trap electrons due to the largest capacity of OH − , Mg-O ion pairs and O 2− on the surface of LDH-3 particles (Fig.…”