Vegetable oils as core of cationic polymeric nanocapsules: Influence on the physicochemical properties

Vegetable oils might be alternatives to mineral or synthetic oils used in nanostructured systems for cutaneous application, due to their advantages with regard to skin care and protection. In this study, we propose the use of vegetable oils (Brazil nut, sunflower seed, olive, rose hip, grape seed and carrot oils) as oily core of Eudragit RS100® nanocapsules and determine their influence on the physicochemical properties of those nanoparticles, in comparison with nanocapsules with capric/caprylic triglycerides as oily core. The formulations containing vegetable oils as core presented pH values suitable for topical application, average diameter close to 280 nm (SPAN around 2.5) and zeta potential close to +7 mV, due to the cationic properties of the polymer. Their viscosities were not affected by the type of oil used as core. By means of multiple light scattering, a reversible particle creaming phenomenon was observed for all the formulations. The nanocapsules prepared using Brazil nut, sunflower seed, olive, grape seed, rose-hip and carrot oils presented some distinct physicochemical properties when compared to nanocapsules obtained with capric/caprylic triglycerides: a higher size and SPAN value, a lower number of particles and a higher tendency to reversible creaming. Those findings are probably related to the lower density and higher viscosity of the vegetable oils. © 2013 Copyright Taylor and Francis Group, LLC.