Argon-plasma-treated chitosan: surface characterization and initial attachment of osteoblasts.

Chitosan is a biocompatible, biodegradable and non-toxic material. It is also an advanced material used for wound dressings, drug and gene delivery, and tissue engineering. In this study, we treated chitosan film with argon plasma and characterized both its physical and chemical properties. We found that argon plasma increased nano-scale roughness and introduced a carbonyl group to the chitosan surface. Meanwhile, the contact angles also decreased as the duration of the plasma treatment on chitosan was prolonged, indicating that the increased roughness and carbonyl group promote the hydrophilicity of the chitosan film surface. Moreover, the number of osteoblasts adhering to chitosan films increased and their morphology became flatter with longer plasma treatments. In conclusion, this study first demonstrates that plasma treatment on chitosan exerting surface-property change is capable of triggering the initial attachment of osteoblasts to chitosan surfaces.