Influence of Different Co-surfactants on the Formation of oil-in-water Microemulsions

Short-chain alcohols were commonly used as co-surfactant in the formulation design of microemulsions.However,the solubility or compatibility of some drugs in these co-surfactants were not satisfactory. Thus,the pseudo-ternary phase diagrams of blank microemulsions with non-alcohol material(Plurol~? Oleique CC 497, Capyrol~(?) 90 or Transcutol~?) as co-surfactant,Labrasol~? as surfactant and Labrafil~? M 1944 as oil were drawn.The results showed that the kind of co-surfactant and the ratio of surfactant/co-surfactant(K_m) could affect the formation of oil-in-water microemulsions.