Novel biodegradable chitin membranes for tissue engineering applications

Chitin is a natural biopolymer that has been investigated for its prospected biomedical applications due to its several biological advantages. However, the chitin is very difficult to dissolve in common solvents due to its rigid crystalline structure. But it is soluble in saturated calcium solvent system under mild conditions. By using the calcium solvent system, chitin regenerated hydrogel (RG) was prepared by using a-chitin. And we also prepared swelling hydrogel (SG) by using beta-chitin with water. In addition, the SG was mixed with glutaraldehyde (GA) or N-acetyl D-(+)-glucosamine (GlcNAc) at 120 degrees C for 2 h. The chitin membranes were prepared by using RG and SG with or without GA or GlcNAc. The prepared chitin membranes were characterized by mechanical, swelling, enzymatic degradation, thermal, and growth of NIH/3T3 fibroblast cell studies. The stress and elongation of chitin membranes prepared from SG with GA or 10%, (w/w) GlcNAc were increased due to the cross-linking effect. The chitin membranes prepared from SG showed higher swelling and degradation than the membranes prepared from RG. Moreover, the chitin membranes prepared from SG with GA or GlcNAc showed lower swelling and degradation than the untreated one. The thermal studies showed that the chitin membranes prepared from RG showed higher thermal stability than the other chitin membranes prepared from SG. And also, these membranes showed good growth of NIH/3T3 fibroblast cells although a little aggregation of cells was observed. So, these chitin membranes are promising biomaterials that can be useful for tissue engineering applications. (C) 2007 Elsevier Ltd. All rights reserved.