ABSTRACT
Objective To prepare two types of biodegradable modified materials (chitosan and collagen)and evaluate whether the new materials are suitable for tissue engineering cartilage.Methods Collagen and chitosan were both modified by poly-γ-benzyl-L-glutamate-co-glutamine acid (PBLG-co-PGA) with different proportions.The contact angle,degradation rate,tensile strength,cell attachment and cytocompatibility were tested and compared.Results As the PBLG-co-PGA content varied,the degradation rates of PBLG-co-PGA composites became adjustable,the hydrophilicity of PBLG-co-PGA/chitosan was improved,and the tensile strength increased in PBLG-co-PGA/collagen composite.The composites with 30％ PBLG-co-PGA were chosen for cytocompatibility and cell attachment experiments.The rabbit condrocytes grew significantly better on PBLG-co-PGA/chitosan than on other three materials(P＜0.05).Conclusion PBLG can improve the hydrophilicity,tensile strength and regulate the degradation rate of composite materials,and the cytocompatibility of the composites with 30％ of PBLG is good,among which PBLG-co-PGA/chitosan can even promote cell proliferation.It could be a new choice of scaffold for tissue engineering cartilage.