Abstract:The bioavailability enhancement of bioactive compounds is an interesting research topic. Sodium tripolyphosphate (STPP) was used as a cross-linking agent to study the structural properties of crosslinked chitosan film and the controlled release property of a crosslinked chitosan-based hydrogel matrix tablet. Chitosan has an abundant source and good biocompatibility. Fourier transform infrared spectroscopy-attenuated total reflectance (FT-IR-ATR) analysis showed that some chemical groups were introduced to chitosan film via crosslinking reactions, which improved the strength of the three-dimensional network structure, and endowed the film with certain swelling and water absorption properties. Meanwhile, the acid resistance of the chitosan film was significantly improved after crosslinking; scanning electron microscopy showed that after transport in simulated gastric fluid (SGF), the surface of the crosslinked chitosan film was still compact with no damage, and it had the potential to be a carrier material for bioactive substances. Moreover, 5-aminosalicylic acid (5-ASA) was used as a model bioactive compound, and a crosslinked chitosan-based hydrogel matrix tablet was prepared by compression. In the simulated release experiment, the release rate of 5-ASA in SGF was dramatically reduced. These results suggest that chitosan crosslinked with STPP could have a wide range of applications in the transport of bioactive substances and the controlled release of drugs.
