Hydrogel-thickened nanoemulsion with green coffee seed oil for topical delivery of vitamin A

Abstract

Nanoemulsions are special emulsions that consist in a very small drop with sizes between 20 to 500 nm. When they are intended for topical application, the main problem of nanoemulsions is their low viscosity, which is reflex of the small drop size. It was proposed the attainment of hydrogel-thickned nanoemulsions with vitamin A palmitate (retinyl palmitate) with green coffee seed oil by phase inversion. Hydrogel-thickned nanoemulsions with drops size ranging between 77 to 110 nm were obtained, depending on the polymer used, with increased viscosity. Rheological profile of developed hydrogel-thickned nanoemulsions was determined, showing the influence of the kind of polymer used, here all presented pseudo-plastic behaviour, with different viscosity measurement. The improvement of the viscosity of the systems, associated with the small droplet size, can be very interesting for vitamin A delivery under the skin.