The effect of surface modification of poly-lactide-co-glycolide/carbon nanotube nanofibrous scaffolds by laminin protein on nerve tissue engineering.

Abstract

The presence of biological cues to promote the attachment, proliferation, and differentiation of neuronal cells is important in the process of nerve regeneration. In this study, laminin as a neurite promoting protein, has been used to modify poly-lactide-co-glycolide/carbon nanotube (PLGA/CNT) electrospun nanofibrous scaffolds by means of either mussel-inspired poly(dopamine) (PD) coating or via direct physical adsorption as a simple route for the functionalization of biomaterials. The laminin-modified scaffolds were characterized by a combination of field emission scanning electron microscopy (SEM), X-ray photoelectron spectroscopy, and contact angle measurements. Subsequently, various properties of scaffolds such as degradation time, amount of attached laminin and the rate of CNT release were investigated. The synergistic effect of topographical and biological cues for PC12 cell attachment, proliferation, and differentiation were then studied by SEM and confocal microscopy. The results of degradation study showed that laminin-modified scaffolds were biodegradable with good structural integrity that persisted about 4 weeks. The amount of laminin attached to the PLGA/CNT and PLGA/CNT-PD scaffolds was 3.12 ± 0.6 and 3.04 ± 071 μg per mg of the scaffold, respectively. Although laminin-modified scaffolds could improve cell proliferation identically, neurite extensions on the PLGA/CNT scaffold modified via PD coating (PLGA/CNT-PD-lam scaffold) were significantly longer than those observed on PLGA/CNT scaffold modified via physical adsorption (PLGA/CNT-lam scaffold) and unmodified scaffolds. Together, these results indicated that surface modification via PD coating could be a promising strategy to fabricate biomimetic scaffolds capable of sustaining longer neuronal growth for nerve tissue engineering.