Alginate-carbon nanotube composites for tissue engineering

Abstract

Biomaterials for cardiovascular tissue engineering should have good mechanical properties to withstand stresses and electrical properties for responding to stimulation. Carbon nanotubes (CNTs) are attractive because of their superior mechanical strength and conductivity. The major issue associated with the use of carbon nanotubes for tissue engineering is their compatibility. This research aims at developing a biocompatible CNT-based alginate scaffold for application in tissue engineering. The CNTs were functionalized and used for the preparation of hydrogels. The difficulties associated with the preparation of the CNT/alginate gel were studied. Composite polymeric hydrogels composing oxidized alginate, protein (either gelatin or collagen) and ingle-walled carbon nanotube (SWCNTs) were investigated. Scanning electron microscope images showed that the composite was highly porous. The biocompatibility of the SWCNTs-containing hydrogel was evaluated by seeding human aortic smooth muscle cells (HASMCs) on it, and a composite without CNTs was used as the control. The results showed that cells could attach to the composite and were found to be living. The longest cell viability (72h) was observed with collagen (5 wt%), oxidized alginate (5 wt%), pristine alginate (1.5 wt%) and SWCNTs (0-1%, w/v). Similar composite hydrogels using gelatin have lower cell viability (24h). CNTs have no effect on the cell viability. From the results obtained, it was concluded that this composite could be used for application in tissueengineering.