Surface modification and characterization of chitosan or PLGA membrane with laminin by chemical and oxygen plasma treatment for neural regeneration

Abstract

Attachment to and proliferation on the substrate are deemed important considerations when Schwann cells (SCs) are to be seeded in synthetic nerve grafts. Good attachment is a prerequisite for the SCs to survive. Fast proliferation will yield large numbers of SCs in a short time, which appears to be promising for stimulating peripheral nerve regeneration. However, surface properties are the dominating factor in influencing the interactions between cells and synthetic nerve grafts. The aim of this study was to investigate the surface effects of laminin modified PLGA and chitosan membranes after chemical method and plasma treatment. Laminin, the extracellular matrix protein, is a permissive protein for SCs adhesion used in neural regeneration. The surface properties of laminin modified membranes were assayed by BCA, FTIR and XPS analysis. Results showed that laminin was covalently bonded onto the surface of both PLGA and chitosan membranes either by chemical method or by oxygen plasma treatment. The cell affinity of the laminin modified membranes was verified by Schwann cells culturing. Our results also indicate that oxygen plasma is indeed a better method to incorporate laminin onto the surface of membrane. Laminin-modified chitosan membrane significantly increases SCs attachment and affinity for directing peripheral nerve regeneration.