Improvement of the electrochemical determination of antioxidant using cationic micellar environment - 10.4025/actascitechnol.v32i4.6945

Resumo

Ascorbic acid (AA) is an important compound of the human diet, in the metabolism acting mainly as exogenous antioxidant. A method for electrochemical detection of Ascorbic acid (AA) with a GCE was developed using a cationic surfactant cetylpyridinium chloride (CPC). The presence of CPC influences the electrochemical behaviour of AA, reduces the applied potential to measure AA oxidation followed by an increase in the peak current. In the optimized conditions the AA determination was possible in the linear range of 5.0 x 10^-7 mol L^-1 - 4.3 x 10^-4 mol L^-1 with a detection limit (S/N = 3) of 2.0 x 10^-7 mol L^-1. The applicability of the method is in the sensitivity and selectivity of the GCE for the AA detection as well as the simplicity of the demonstrated method using an electrode without modifying and without pre-treatment of samples. Recovery tests presented values of 98 - 103% suggesting the method has no significant interference and making possible to be successfully used for AA determination in complex samples.