Nanoencapsulation of buriti oil: influence of formulation variables through experimental design

The nanoencapsulation of buriti oil enhances skin coverage and potentiates its antioxidant and wound-healing activities by protecting bioactive compounds and improving topical application. This study aimed to optimize nanocapsule formulations through experimental design. A full 2³ factorial design was employed, varying the concentrations of surfactant (0.15 to 0.75 g), polymer, and buriti oil, generating 18 formulations. Nanocapsules were prepared by interfacial polymer deposition and characterized by dynamic light scattering and electrophoretic mobility to determine mean diameter, polydispersity index (PDI), and zeta potential. Formulations that exhibited phase separation typically contained higher amounts of oil and surfactant. The second-order polynomial model best described the effects of formulation variables. Surfactant and oil content significantly influenced particle size, while zeta potential remained largely unaffected by the independent variables. Lower surfactant concentration (0.15 g) led to larger particle diameters but increased homogeneity, as shown by PDI. Higher surfactant amounts (0.75 g) reduced diameter but did not always prevent phase separation in formulations with more oil. Zeta potential results varied irregularly, indicating limited influence of polymer and surfactant concentration. These findings underscore the importance of optimizing surfactant and oil levels to achieve stable nanocapsules with desirable characteristics. Experimental design proved effective in identifying relevant formulation parameters and can guide future improvements in nanoformulations for dermocosmetic applications.