title: Evaluating protein incorporation and release in electrospun composite scaffolds for bone tissue engineering applications.
abstract: Electrospun polymer/ceramic composites have gained interest for use as scaffolds for bone tissue engineering applications. In this study, we investigated methods to incorporate Platelet Derived Growth Factor-BB (PDGF-BB) in electrospun polycaprolactone (PCL) or PCL prepared with polyethylene oxide (PEO), where both contained varying levels (up to 30 wt %) of ceramic composed of biphasic calcium phosphates, hydroxyapatite (HA)/β-tricalcium phosphate (TCP). Using a model protein, lysozyme, we compared two methods of protein incorporation, adsorption and emulsion electrospinning. Adsorption of lysozyme on scaffolds with ceramic resulted in minimal release of lysozyme over time. Using emulsion electrospinning, lysozyme released from scaffolds containing a high concentration of ceramic where the majority of the release occurred at later time points. We investigated the effect of reducing the electrostatic interaction between the protein and the ceramic on protein release with the addition of the cationic surfactant, cetyl trimethylammonium bromide (CTAB). In vitro release studies demonstrated that electrospun scaffolds prepared with CTAB released more lysozyme or PDGF-BB compared with scaffolds without the cationic surfactant. Human mesenchymal stem cells (MSCs) on composite scaffolds containing PDGF-BB incorporated through emulsion electrospinning expressed higher levels of osteogenic markers compared to scaffolds without PDGF-BB, indicating that the bioactivity of the growth factor was maintained. This study revealed methods for incorporating growth factors in polymer/ceramic scaffolds to promote osteoinduction and thereby facilitate bone regeneration.
authors.affiliation: Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, New Jersey, 07102.
authors.forename: Tonye
authors.initials: T
authors.lastname: Briggs
authors.affiliation: Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, New Jersey, 07102.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Matos
authors.affiliation: Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, New Jersey, 07102.
authors.forename: George
authors.initials: G
authors.lastname: Collins
authors.affiliation: Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, New Jersey, 07102.
authors.forename: Treena Livingston
authors.initials: TL
authors.lastname: Arinzeh
mesh_terms: D000077214:Becaplermin; D002130:Calcium Phosphates / Q000737:chemistry; D002478:Cells, Cultured; D002516:Ceramics / Q000737:chemistry; D003692:Delayed-Action Preparations / Q000737:chemistry / Q000493:pharmacokinetics; D017886:Durapatite / Q000737:chemistry; D006801:Humans; D006882:Hydroxyapatites / Q000737:chemistry; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000378:metabolism*; D009113:Muramidase / Q000737:chemistry / Q000494:pharmacology; D011091:Polyesters / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D020574:Proto-Oncogene Proteins c-sis / Q000737:chemistry / Q000493:pharmacokinetics; D023822:Tissue Engineering; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D002130:Calcium Phosphates; D003692:Delayed-Action Preparations; D006882:Hydroxyapatites; D011091:Polyesters; D020574:Proto-Oncogene Proteins c-sis; C485817:beta-tricalcium phosphate; C074950:hydroxyapatite-beta tricalcium phosphate; D000077214:Becaplermin; C016240:polycaprolactone; D011092:Polyethylene Glycols; D017886:Durapatite; D009113:Muramidase
keywords: PDGF-BB; electrospinning; mesenchymal stem cells; protein release; surfactant