Abstract

CHITOSAN-ALGINATE HYDROGEL BEADS AS CARRIER TO ALBUMIN EVALUATED IN VITRO FOR ORAL PROTEINS ADMINISTRATION

Rebecca Torelli-Souza, Josefa Lopes-Ferreira, Taynara Batista-Lins, Larissa Monteiro and Rosa Valéria Amorim*

ABSTRACT

The oral-colon specific drug delivery is one of the most promising ways to increase the bioavailability of many bioactive compounds and nowadays chitosan (CS) and alginate (AL) plays a very important role in the pharmaceutical industry. In this study we comparatively investigate the in vitro release of bovine serum albumin (BSA), through CS and CS-AL hydrogel beads, and the effect of pH related swelling on the release of the protein for potential applications in oral protein delivery. The pH-sensitive hydrogel beads composed of chitosan (CS) and alginate (AL) were developed by coacervation and were characterized by morphology, swelling ratio and FT-IR spectrum analyses. The releases profile assays were analyzed in vitro in simulated gastric fluid (SGF) and simulated colonic fluid (SCF), using an orbital shaker at 100 rpm and 37°C and studies of swelling properties of beads were also investigate in same condictions. The morphological characterization shown CS-AL hydrogel beads, display a smoother surface, when compared with CS beads and regarding internal stucture, CS beads seems sponge-like in comparison with CS-AL hydrogel beads, which have an uniform matrix and a lower porosity. The profile of the absorption spectrum of hydrogels shows changes in the modes of peak vibrations when compared to isolated polymer spectrums suggests the formation of the polyelectrolyte complex between CS and AL. The hydrogel beads remained stable in an acid medium with an average size of approximately 1000 μm. BSA delivery in hydrogel beads using 10 mg/mL of protein was sustained for SCF, but delayed for SGF, remaining stable in this medium. According the results, CS-AL hydrogel beads were pH-sensitive and could be employable in oral delivery systems for therapeutic proteins.

Keywords: Chitosan; alginate; hydrogel; colon delivery; oral administration.