Production and characterisation of poly (L-lactic acid) / graphene oxide nanofibers for nerve regeneration

Abstract

The development of biodegradable polymeric nanofiber scaffolds for a potential effort to repair injured nerve cells attracts great interest in nerve tissue engineering field. Poly (L-lactic acid) (PLLA) has being widely used in development of nerve fiber studies due to its biocompatibility, easily shaped properties and degradation to low toxic lactic acid. However, its hydrophobicity and lack of binding sites for cellular activities restricts its use as implants. In this regard, this study involves the incorporation of Graphene Oxide (GO) into PLLA either electrospun GO with PLLA or coating GO onto the PLLA and PLLA/GO nanofibers to fabricate ideal scaffolds with appropriate physical, mechanical and chemical properties of nanofiber mimicking the properties of the peripheral nerve. Hence, PLLA and PLLA/GO nanofibers were prepared via processing PLLA and PLLA/GO solutions with electrospinning and solution parameters (the concentration of PLLA, GO ratio and composition of binary system) were optimized to obtain thin and bead free nanofibers. Then, the fabricated nanofibers were functionalized with 1,6-Hexamethylenediamine (HMDA) and then coated with GO sheets. The fabricated PLLA, PLLA/GO and GO coated PLLA and PLLA/GO nanofibers were characterized via Light Microscopy, Scanning Electron Microscopy (SEM), Raman Spectroscopy, Ninhydrin assay, X-Ray Photoelectron Spectroscopy (XPS), tensile test and Water Contact Angle (WCA) measurement. The characterization results revealed that addition of GO either as filler or coating material enhanced physical, mechanical and chemical properties of nanofiber scaffold. In conclusion, the developed nanofiber scaffolds are promising for possible nerve regeneration application.|Keywords : Poly (L-lactic acid) (PLLA), Graphene Oxide (GO), 1,6-Hexamethylenediamine (HMDA), Nerve Regeneration.