Abstract:
This research study the development of microemulsion formulations containing
Angelica sinensis root extract that does not rely on high technology tools. First, the experiment
started with determination of the proportion of surfactant, oil, and water and constructed the
ternary phase diagram. There were two non-ionic surfactants which were cremophor RH40 and
tween 20. These two emulsifiers have hydrophilic lipophilic balance (HLB) in the range of 14-
16.7. For the oil phase, clove oil, peppermint oil, neroli oil and sage oil were used at a constant
ratio and the 1% Angelica sinensis root extract was added in the oil phase. The ternary phase
diagram were prepared by using distilled water as a continuous phase to obtain microemulsion.
For example, the composition of surfactant : oil : water (4: 1: 5) was prepared by adding Angelica
sinensis root extract (0.1 g) to the clove oil (2 g) and tween 20 (8 g); then mixed together with a
vortex mixer and water (10 g) was added and mixed to obtain a clear transparent liquid flow and
physical-chemical stability microemulsion. All ternary phase diagram of 4 oils were constructed
and calculate the percentage area of microemulsion. The selected compositions of microemulsions
were measured the particle sizes and electrical potentials with the Zetasizer model S4700
(Malvern, UK). All microemulsions were measured the viscosity and pH values. The selected
formula of microemulsion was subjected to the penetration study by the in vitro process. Using the
dorsal skin the baby pig with franz diffusion cell, the experiment used microemulsion water in oil
type (O/W, 4: 1: 5) with particle size that equaled to 13 ± 0.0 nm and zeta potential equaled to -6.6
± 1.6 mV. The pH value of the microemulsion equaled to 6.7 and the viscosity was 208.23 cPs.
The flux of ferulic acid absorption was 852.9 ± 14.6 mcg / min.cm2 and permeability rate was 3.83
± 0.07 × 10-3 cm / min.