Curcumin-loaded polysaccharides-based complex particles obtained by polyelectrolyte complexation and ionic gelation. I-Particles obtaining and characterization.

Curcumin has essential therapeutic benefits, but it is insoluble in water and thus has low bioavailability. This study aimed to immobilize curcumin into new polysaccharide-based microparticles (gellan, i-carrageenan, and chitosan) to increase its stability and bioavailability. Curcumin-loaded complex microparticles were obtained from three polysaccharides, of different ionic character, by ionic cross-linking and polyelectrolyte complexation. The immobilization efficiency was between 85.75% and 97.25%. The microparticles were characterized morphologically by SEM, and it was observed that the microparticles containing the i-carrageenan had a more pronounced porosity of the matrix. The swelling degree values at pH = 7.4 were superior to those obtained at pH = 6.8 or pH = 2 and depend on both the cross-linking degree and particles morphology. The polysaccharides microparticles, curcumin, and constituent polysaccharides were characterized by FT-IR spectroscopy. The curcumin release kinetics was studied in three different pH media, and the release efficiency ranged between 65.1% and 97.9% at pH = 7.4, between 60.2% and 82.2% at pH = 6.8 and between 56.1% and 64.0% at pH = 2. These microparticles can be intended for oral administration, having as therapeutic target the colon, for the controlled release of curcumin, since they can overcome the gastric barrier without the degradation of the active principle, which is protected by the polymer matrix.