Where; A is absorbance of diluted sample,
MW is molecular weight of cyaniding-3-glucoside
(449.2 g/mole), DF is dilution factor, ε is the molar
absorptivity of cyanididn-3-glucoside (26,900
mole/L) and W is weight of Roselle dried extract (g),
respectively.
Preparation of liposome formulations
Liposome dispersion samples were prepared
by a modified ethanol injection technique(25). Liposomes
containing Roselle extract (10% w/v) were formulated
by optimizing types and ratios of lipid composition, as
well as the total lipid contents. Each material was
accurately weighed and placed into two separate
vessels, one for the lipid phase and another for the
water phase. The lipid phase consisted of a mixture of
lipid, additive, surface charge and the extract in 95%
ethanol (10 mL). The water phase was acetate buffer
pH 5.5 (10 mL). The temperature of both phases was