Ability of Chitosan/Carrageenan Complex to Encapsulate Bovine Serum Albumin (BSA) for Potential use in Protein Delivery

The purpose of this study was to examine the capability of chitosan/carrageenan complex formed by electrostatic interaction as a carrier system for protein delivery. Chitosan/carrageenan complex was formulated at charge ratios (+/-) of 1,3,5,7 while bovine serum albumin (BSA) was the model protein. Microencapsulation of BSA was carried out by mixing BSA with chitosan solution o followed by -, -, or -carrageenan then agitated at 200 rpm for 24 hours at 4^oC. The resulting complex was then evaluated by different physical methods. Results showed that the polyelectrolyte complex with -carrageenan had the highest encapsulation efficiency at 74 % with the order of >> and was stable in pH 1.2 to 7.3. The complex of chitosan/carrageenan was more efficient in the encapsulation of BSAthan using chitosan or carrageenan alone. Controlled release of BSAfrom the complex was observed when treated with enzymes and different physiological solutions. Among the complexes prepared, chitosan/-carrageenan complex was the most stable releasing the BSAat the lowest rate. SDS-PAGE analysis of the complex showed no degradation of BSAwhen exposed in pH 1.2 solution 37^oC for 1 hour while gradual degradation was observed in pepsin solution (1 mg/mL). Zeta potential ranged from -40 mV to -50 mV with z-average size from 334 nm to 782 nm. Atomic Force Microscopy (AFM) images of chitosan/carrageenan complex loaded with BSA showed compact structure with almost uniform circular structure.