Sustained Release of Proteins from Electrospun Biodegradable Fibers

TLDR

Electrospinning produces polymeric fibers from submicron to micron diameters and can incorporate bioactive agents to create biofunctional tissue engineering scaffolds. The study examined whether human β‑nerve growth factor could be encapsulated in a PCLEEP copolymer via electrospinning. Human β‑nerve growth factor was stabilized in bovine serum albumin and encapsulated within a PCLEEP copolymer using electrospinning. The electrospun fibers released NGF over at least three months, with the protein randomly dispersed in aggregates, and retained bioactivity as shown by PC12 neurite outgrowth, demonstrating the feasibility of protein encapsulation for biofunctional scaffolds.

Abstract

Electrospinning is a simple and versatile technique of producing polymeric fibers ranging from submicron to micron in diameter. Incorporation of bioactive agents into the fibers could make a biofunctional tissue engineering scaffold. In this study, we investigated the feasibility of encapsulating human β-nerve growth factor (NGF), which was stabilized in a carrier protein, bovine serum albumin (BSA) in a copolymer of ε-caprolactone and ethyl ethylene phosphate (PCLEEP) by electrospinning. Partially aligned protein encapsulated fibers were obtained and the protein was found to be randomly dispersed throughout the electrospun fibrous mesh in aggregate form. A sustained release of NGF via diffusion process was obtained for at least 3 months. PC12 neurite outgrowth assay confirmed that the bioactivity of electrospun NGF was retained, at least partially, throughout the period of sustained release, thus clearly demonstrating the feasibility of encapsulating proteins via electrospinning to produce biofunctional tissue scaffolds.