Effect of the HLB values of non-ionic surfactants on size and size distribution and stability of oil/water soybean oil nanoemulsions:(TJPS-2020-0082.R1)

Abstract

Objective: This study aims at investigating the effect of the HLB of non-ionic surfactants on physical property and stability of nanoemulsions. Material and Methods: The nanoemulsions were prepared by using the Microfluidizer. The oil phase consisted of 10% w/w soybean oil and 5% w/w surfactant(s). Types of nanoemulsions were confirmed by dilution test. The average droplet size and size distribution (PDI) were measured by dynamic light scattering Zetasizer Nano ZS™. The screening physical stability was done by centrifugation. Only the formulations with no phase separation was further evaluated for physical stability. Results: All nanoemulsions were single phase turbid liquids with no intrinsic creaming. The formulation with HLB 15 showed significantly larger droplet size followed by HLB 10, 9, 8 and 4.3, respectively. The PDI values were in range of 0.071-0.117. All nanoemulsions regardless of the HLB values showed no significant change in droplet size and the Ostwald ripening rates were almost zero. Conclusion: The formulation with the mixed surfactants of HLB 8 seems to be promising for the future development of cosmetics because this nanoemulsion had the smallest droplet size which could enable efficient actives movement to the skin because of its remarkably high surface area.

:TJPS-2020-0082.R1