CamSep 5 S

VARIOUS ELECTROANALYTICAL ASSAYS USED FOR THE
DETERMINATION OF TOTAL ANTIOXIDANT POTENTIAL (TAP)
IN FOOD
Bronisław K. GŁÓD, Iwona KIERSZTYN, Paweł WANTUSIAK, Paweł PISZCZ
Siedlce University of Natural Sciences and Humanities
Department of Analytical Chemistry ul. 3 Maja 54, 08-110 Siedlce; Poland
URL: dach.ich.uph.edu.pl, e-mail: psc1@onet.eu
Free radicals play an important role in living organisms. Most of them are very reactive,
usually characterized by strong oxidizing properties. They are the reason, transition step, product or
side-effect of many diseases and aging. Excess of them and/or oxidants are removed by the
scavengers of free radical or antioxidants, respectively. The both terms are often used alternatively.
It turns out that the antioxidant properties of real samples are often better described by the, so
called, total antioxidant potential (TAP), although other names are also used. It is proportional to
the sum of the products of the concentrations and reaction rate constants of all antioxidants in the
sample. In the presentation new, elaborated by us, TAP assays are discussed.
In cyclic and differential pulse voltammetry the TAP measure is peak surface area measured
in special coordinates. Much more sensitive measurements can be obtained using the
electrochemical detection in HPLC. Described in the literature TAP assays are usually based on the
kinetic photometric measurements. The stable, or generated, radicals react competitively with the
test sample and the so-called sensor. TAP measure is the induction time of photo- or fluorometric
signal. Improved assays related to the peroxyl or DPPH radicals are discussed. The
chromatographic TAP measurements are static techniques. The TAP measure is decrease of the
surface area of chromatographic peak of the reaction product of radical with sensor. Its value refers
to the hydroxyl radicals, the strongest natural oxidant/radical.
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