Construction of alternate layered chitosan/alginate composite hydrogels and their properties

Novel alternate layered chitosan/alginate composite hydrogels (CACH) were fabricated successfully by a multi-step alternate interrupted gelation process. The structure and properties of the hydrogels were characterized. The results indicated that the shape, size and layer thickness could be controlled by changing the gel core shape, chitosan/alginate concentration and soaking time. The CACH exhibited good architectural stability. Endothelial cells could adhere and proliferate on the layer surface, showing great potential as cell culture carriers and matrix for the control release of molecules due to the distinct physical barriers. This work opens up a new avenue for the construction of other polymer based alternate layered hydrogels.