New Curcumin-Loaded Chitosan Nanocapsules: In Vivo Evaluation

The medicinal applications of curcumin, the major component of <i>Curcuma longa</i>, are limited by its poor solubility and low oral bioavailability. In order to overcome this limitation, a method to produce nanocapsules of chitosan loaded with curcumin was developed. Three different molecular weight and deacetylation degree chitosan polymers were used in the formulation in order to prepare curcumin-loaded nanocapsules (mass ratio 1 : 1.4). The best results were achieved using chitosan-Bi with a molecular weight of 710 000 Da. A bimodal distribution was observed in samples; moreover, chitosan-Bi produced the lowest particle size (197 nm). The entrapment efficacy of all chitosan nanocapsules produced reached values between 75 and 92 %. Their rate of drug release at different pH levels (2.0 and 7.4) showed a fast onset of curcumin release. Swiss mice were used to determine oral and total bioavailability of the new curcumin-loaded nanocapsules. Remarkably, the bioavailability of curcumin nanoformulated increased 9-fold compared with no formulated curcumin. These nanocapsules have the ability to cross the blood-brain barrier, and its production is an easy to scale-up procedure using nontoxic materials.