Leal, Guilherme Carneiro, et al. Research, Society and Development 11.16 (2022).
The demand for natural, sustainable, and skin-compatible topical formulations is growing significantly in both the cosmetic and pharmaceutical compounding sectors. This study examined the role of sodium stearoyl glutamate as a functional anionic co-emulsifier in optimizing the properties of oil-in-water (O/W) natural emulsions intended as vehicle bases for topical preparations.
Formulation Development: Sodium stearoyl glutamate was evaluated as a co-emulsifier in conjunction with three different non-ionic, self-emulsifying waxes of natural origin. Nine O/W emulsion formulations were developed, with the primary variable being the type of primary emulsifying base, used either alone or in combination with Sodium Stearoyl Glutamate. All formulations were prepared using standard hot-process emulsification and contained ingredients certified for natural cosmetics.
Key Findings:
· The association of this anionic co-emulsifier with a primary emulsifier (cetearyl olivate (and) sorbitan olivate) resulted in the most stable formulation (FB1). FB1 passed accelerated stability studies, while other formulations without this combination showed inferior long-term stability.
· The use of the co-emulsifier contributed to beneficial characteristics such as reduced particle size, increased viscosity, and desirable pseudoplastic, thixotropic flow behavior with yield strength. The selected FB1 formulation exhibited a skin-compatible pH (5.14) and was classified as "skin friendly".
· The in vivo bioengineering study confirmed that FB1 significantly improved skin hydration over 28 days of application compared to an untreated control. While it did not significantly alter TEWL, values remained within an ideal range.
Aydınlı, Elif, et al. International Journal of Traditional and Complementary Medicine Research 4.2 (2023): 68-78.