Biopolymers have important role in oral delivery of protein drugs because of biocompatibility and their nontoxicity. Biopolymers such as chitosan, alginate and dextran are common polymers in drug delivery systems. Alginate-chitosan nanoparticles synthesized by the gelation method and different ratios of alginate and chitosan solutions were used. At first, chloride calcium added dropwise to alginate and then chitosan to them to form a gelatinous state. Sediment were separated and dried in 50˚c and then the sample dissolved in different buffers (pH: 1.2, 5, 7.4) for determination of swelling rate. DLS and FT-IR spectrum measured for characterization of nanoparticles containing amylase. Results showed that rate of swelling in different pH had considerable differences, while nanoparticles sediments are not swelled in acidic pH but well swelling observed in alkaline pH. The release enzyme rate during different times indicated that with increasing time, a greater amount of enzyme released. The functional groups in this nanoparticles confirmed by the FT-IR spectrum and the formation of nanoparticles on a nanoscale was well confirmed by DLS. Conclusion; synthesized nanoparticles have a good ability for enzyme encapsulation, therefore such nanoparticle could be used for oral delivery.
