Biomedical Engineering Reference
In-Depth Information
Fig. 8
Antioxidant activities of quercetin (
ı
) and CBC membrane loaded with quercetin and
thymol by SSI at 20 MPa and 323 K (
). Enclosed picture represents the control and the membrane
system after 8 h of oxidative reaction
antioxidant system by measuring its capacity to be oxidized preferentially avoiding
the oxidation of
“
-carotene. After starting the oxidative reaction, the oxidation
“
of
-carotene is followed by measuring the color of the solution at specific time
intervals at 470 nm. The samples presenting higher color intensity correspond to the
ones that have higher antioxidant capacity. The method was applied in this work to
investigate the antioxidant activity of the CBC membranes impregnated at 20 MPa
and 313 K. The procedure was similar to the one reported in the literature, where the
extract was substituted by a sample of impregnated membrane. Figure
8
compares
de results obtained for an ethanolic mixture of quercetin and thymol with the ones
obtained for the CBC loaded membranes. Results show that for the monitored
period, the impregnated membrane is able to inhibit the oxidation of
“
-carotene by
almost 50%. The trend is dependent on the release of quercetin from the membrane
what justifies the lower value observed at the first hour where only 40% of the total
loaded amount was delivered to the reaction medium. Unfortunately, the method
did not permit to follow the reaction for longer periods as the slow dissolution
of the polymeric matrix causes dispersion that interferes with the colorimetric
method. However, visual observation after 8 h (photo attached to Fig.
8
) permits
to conclude that the membrane presents a prolonged antioxidant activity what can
be advantageous for long term wound healing processes.
