Temperature-insensitive microemulsions formulated from octyl monoglucosideand alcohols: potential candidates for practical applications

Microemulsion formulations based on non-toxic alkyl glucosides (C(m)G(n)) a re of interest for applications in pharmaceutical and cosmetic products. In this work we demonstrate the favorable properties of quaternary microemuls ions consisting of water oil - C(8)G(1) - alcohol. As alcohols we used n-oc tanol as well as the non-toxic geraniol (C10H17OH). Microemulsions with ger aniol are potential candidates for pharmaceutical applications We show for the first time by simultaneous phase behavior, SANS and interfacial tension measurements a quantitative correlation between the curvature and the comp osition of the interfacial film. We can relate the behavior of quaternary, temperature-insensitive microemulsions based on alkyl glucosides to that of ternary nonionic systems which exhibit a temperature-dependent curvature o f the film. Thus, we are able to compare directly the effect of the tempera ture and the concentration of alcohol in the interfacial film. Both are imp ortant tuning parameters for the curvature, helping to formulate microemuls ions with the desired properties in practical applications.