Polycaprolactone and bovine serum albumin based nanofibers for controlled release of nerve growth factor

Tissue engineering approaches for peripheral nerve regeneration employ biodegradable scaffolds coupled with growth factors for improved performance in regeneration of large nerve injuries. Electrospun nanofibers provide a versatile platform for fabrication of scaffolds with extracellular matrix like architecture and increased surface area. Incorporation of growth factors in nanofibers have been previously demonstrated using oil in water emulsion techniques but are associated with burst release and loss of valuable growth factor. Here, we show a novel blend of polycaprolactone and bovine serum albumin (BSA) to form nanofibers containing nerve growth factors. The BSA helps in overcoming the most common drawbacks associated with hydrophobic polymers such as reduced loading efficiency, long degradation periods, and burst release. The controlled release of nerve growth factor (NGF) from the nanofibers was evaluated using enzyme linked immune sorbent assay (ELISA) and PC12 based bioassay over a 28 day time period. A sustained release of NGF was obtained for at least 28 days. PC12 bioassays confirmed the bioactivity of the NGF, and showed that the released NGF was sufficient to induce neurite outgrowth from PC12 cells throughout the period of release, therefore, demonstrating the successful incorporation and controlled release potential of PCL BSA scaffolds.