Chitosan Coated Alginate Microparticles for Oral Vaccine Delivery

The aim of this study was to prepare Caalginate and chitosan (CS)Caalginate microparticles for peroral delivery of ovalbumin (OVA). Microparticles containing different loading of OVA (10, 20 and 40 % w/w) were prepared by cross-linking alginate with calcium chloride using an electrohydrodynamic spraying technique, and then coated with CS. The particle sizes of OVA-loaded microparticles were in the range of 1-5 µm. The negative charge was obtained for Caalginate microparticles (-14±1.9 mV) whereas CSCaalginate microparticles were positive charge (+6.06±3.4 mV). Caalginate microparticles with initial 20% w/w OVA showed the highest entrapment efficiency and amount of OVA content (24.91±0.4% and 33.22±0.1 mg/g, respectively) as similar to CSCaalginate microparticles with initial 20% w/w OVA that showed the highest entrapment efficiency and amount of OVA content (35.74±0.1% and 10.35±0.5 mg/g, respectively). It was found that the release rate of OVA from Caalginate microparticles was higher than CSCaalginate microparticles, and the lowest release rate, sustained release for 24 h, was found in the initial 40% w/w OVA. This study revealed that CSCaalginate microparticles have a considerable potential as controlled release antigen delivery systems.