Microparticle-hydrogel hybrids for sustained release of dual bioactive compounds

A novel Cur/TPP-beta-CD/CS/Vc microparticles (MPs) filled CMCS/OSA composite hydrogel was prepared by dispersed the chitosan/vitamin C (CS/Vc) complex and curcumin/TPP-beta-cyclodextrin (Cur/TPP-beta-CD) complex in the hydrogel precursor of oxidized sodium alginate (OSA) and carboxymethyl chitosan (CMCS). Structural properties of the MPs/CMCS/OSA composite hydrogel were characterized by Fourier transform infrared, scanning electron microscope, TG, rheological, and texture analyzer. It was found that the polymeric MPs with a diameter of about 2.5 mu m were homogenously embedded in the composite hydrogel by hydrogen bonding and electronic force, resulting in obvious enhanced mechanical strength and stability of the MPs hybrid hydrogel. In vitro release studies show that the release of Cur and Vc can be more efficiently controlled by the different encapsulation pathways. Moreover, the preferential release of the Cur than that of Vc has been confirmed by the two-dimensional ultraviolet correlation spectroscopy. Therefore, the MPs/CMCS/OSA composite hydrogel can be used for independently controlled release of dual bioactive compounds during codelivery.