Single Component Chitosan Microcapsule from a Layer-by-layer Approach-Yongjun Zhang

A strategy for the fabrication of single component hollow gel capsules from LbL assembly was proposed. It involves an initial selective cross-linking of one component followed by removal of the second component for the LbL assembly. This strategy was confirmed by the successful synthesis of single component chitosan gel microcapsules. The cross-linking of chitosan increased the film stability and make it strong enough to resist osmotic force during the removal of the sacrificial core. The resultant chitosan hydrogel capsules were pH sensitive. They swelled at low pH and shrank at high pH. The cross-linking density of the capsule wall can be controlled and has a significant effect on its pH sensitive behavior.