A cosmetic patch containing tamarind fruit extract
was formulated and developed by blending two types
of natural polymers: chitosan with molecular weight
ofv100000 and starch such as corn, potato or tapioca
starch. The physicochemical characteristics, i.e. flexibility, colour, transparency, integrity, gloss, water
sorption and bioadhesion property and the stability
of the patch without tamarind content were investigated. Stability test was performed by keeping the
prepared patches at 4 8C, at room temperature or at
45 8C for 2 weeks.The results showed that the formu-
lations composed of chitosan:corn starch ratio of
4.5 : 0.5 (CC4.5 : 0.5) and chitosan:tapioca starch ratios
of 4.5 : 0.5 (CT4.5 : 0.5) and 4.0 : 1.0 (CT4 : 1) provide
patches with favourable physical characteristics,
high water sorption, good bioadhesion ability and
good stability. After the lyophilized tamarind extract
in an amount corresponding to 5% of tartaric acid
was incorporated into the formulations of CC4.5 : 0.5,
CT4.5 : 0.5 and CT4 : 1, the ability of the patches to
adhere to skin was improved. However, after keeping
the test patches at room temperature or at 45 8C for
6 weeks, their colours were intensified while their
flexibilities and skin adhesion properties decreased.
A 12-h in vitro permeation was investigated by
studying the cumulative amount of tartaric acid