Preparation, characterization and antioxidant activity of nanoemulsions containing ascorbyl palmitte

Resumo

Ascorbyl palmitate (or L-ascorbyl-6-palmitate), which is a more stable fat-soluble derivative of vitamin C, may be an agent for incorporation into topical formulations. Its main advantage is the vitamin C-type antioxidant capacity, which may be compromised due to the physicochemical instability of this active agent against photodegradation. Nanotechnology is an alternative found to improve stability and to prevent degradation of ascorbyl palmitate. Thus, the objective of this work was to develop, characterize and evaluate the antioxidant activity of ascorbyl palmitate-containing nanoemulsions. The nanoemulsions were prepared by the high and low energy method, and the results of the physicochemical characterization were 104 nm in diameter for the ascorbyl palmitate containing nanoemulsions prepared by the high energy method (T - NE - MP) and 168 nm for nanoemulsions prepared by the low energy method (R-NE-MP), a polydispersity index of 0.18 (T - NE - MP) and 0.312 (R-NE-MP), zeta potential of -18.88 mV (T - NE - MP) and -22.16 mV (R-NE-MP), pH 3.81 (T - NE - MP) and 3.93 (R-NE-MP) and morphology showed globular droplets. The content result was 100 % ± 1.42 for R-NE-MP. The antioxidant capacity of ascorbyl palmitate-containing nanoemulsions obtained by the low energy method was superior to the two associated free actives and was equivalent to palmitate activity free. The results demonstrate the viability of encapsulation of ascorbyl palmitate. The nanoemulsions prepared by the low energy method can be a strategy to obtain stable and effective cosmetic formulations.