The antioxidant barrier system of the skin acts as the main defence against environmental
pro-oxidants. Impaired skin oxidative state is linked to unhealthy conditions such as skin autoimmune
diseases and cancer. Thus, the evaluation of the overall oxidative state of the skin plays a key role
in further understanding and prevention of these disorders. This study aims to present a novel ex
vivo model to evaluate the skin oxidative state by the measurement of its antioxidant capacity (AOC).
For this the ORAC assay was combined with classical tape stripping and infrared densitometry to
evaluate the oxidative state of the stratum corneum (SC). Outcomes implied the suitability of the
used model to determine the intrinsic antioxidant capacity (iAOC) of the skin. The average iAOC of
untreated skin was determined as 140 +- 7.4 M TE. Skin exposure to UV light for 1 h reduced the
iAOC by about 17%, and exposure for 2 h decreased the iAOC by about 30%. Treatment with ascorbic
acid (AA) increased the iAOC in a dose-dependent manner and reached an almost two-fold iAOC
when 20% AA solution was applied on the skin. The application of coenzyme Q10 resulted in an
increase in the iAOC at low doses but decreased the iAOC when doses > 1% were applied on the skin.
The results show that the combination of classical tape stripping and ORAC assay is a cost-effective
and versatile method to evaluate the skin oxidative state and the pro-oxidate and antioxidative effects
of topical skin treatments on the iAOC of the skin. Therefore, the model can be considered to be a
valuable tool in skin research.