A Water in Oil Gelled Emulsion as a Topical Release Vehicle for Curcumin

The objective of this work is to assess the influence of the concentration of polyglycerol polyricinoleate (PGPR) (at 1%, 1.5%, and 2%) on the physical properties of water in oil gelled emulsions (W/O) and evaluates their efficiency as a delivery vehicle for curcumin. Emulsions are characterized by drop size, centrifugal test, texture, and rheology during 28 days of storage. When the surfactant concentration increases, smaller droplet sizes are obtained (<5 mu m), the phase separation (tested by centrifugal force) decreases from 6% to 4% with little variation of the time. The mechanical properties of emulsions show a tendency to decrease as time passed and concentration of PGPR increased. The emulsions increased viscosity as the concentration increased, but the addition of curcumin reduce the viscosity of the emulsions. About controlled release profiles, a low concentration of PGPR shows an increase in the affinity between curcumin and the emulsions, following a pseudo-Fickian release behavior. At higher concentration of PGPR shows a decrease in the affinity between curcumin and the emulsion, displaying a Fickian release behavior. The authors were able to prepare tailor made curcumin water in oil emulsion systems for the topical release of this compound.