Abstract The purpose of the present study
was to investigate the effect of different oil and chain lengths of
co-surfactant on microemulsion region. Oleic acid and isopropyl myristate were
used as the oil phase, transcutol, polyethylene glycol 400 (PEG 400) and
propylene glycol as co-surfactant and Brij 97 as a surfactant. From the ternary
phase diagrams, isopropyl myristate based system is more feasible oil phase to
formulate microemulsion compared to oleic acid based system. Moreover,
transcutol (medium chain length) is the most suitable co-surfactant to blend
with a single-chain surfactant, Brij 97 in order to have a high stability and a
large area of microemulsion region.
Keywords: microemulsion, oleic acid,
isopropyl myristate, transcutol, propylene glycol
