Because the LMWAs have electronegativity, they can be measured
using electrochemical methods [16], very attractive because
of their experimental simplicity, low cost, and high sensitivity [17].
In this sense, both amperometric and voltammetric methods havebeen used to measure the antioxidant capacity of biological samples.
Amperometric methods are suitable and have been used to
determine the activity of antioxidant enzymes and some LMWAs
[18–23]. Voltammetry is able to quantify hydrophilic and lipophilic
LMWAs within a concentration range of 110 lmol/L, suitable for
measuring antioxidant concentrations in biological samples
[24–32]. However, the high concentrations of proteins that adhere
to the electrode can interfere with the result. To resolve this
problem, before each measure, the electrode must be polished to
maintain the sensitivity, and this procedure increases the time to
take the measurements [25,26].