title: Additive Manufacturing of a Photo-Cross-Linkable Polymer via Direct Melt Electrospinning Writing for Producing High Strength Structures.
abstract: Melt electrospinning writing (MEW) is an emerging additive manufacturing technique that enables the design and fabrication of micrometer-thin fibrous scaffolds made of biocompatible and biodegradable polymers. By using a computer-aided deposition process, a unique control over pore size and interconnectivity of the resulting scaffolds is achieved, features highly interesting for tissue engineering applications. However, MEW has been mainly used to process low melting point thermoplastics such as poly(ε-caprolactone). Since this polymer exhibits creep and a reduction in modulus upon hydration, we manufactured scaffolds of poly(L-lactide-co-ε-caprolactone-co-acryloyl carbonate) (poly(LLA-ε-CL-AC)), a photo-cross-linkable and biodegradable polymer, for the first time. We show that the stiffness of the scaffolds increases significantly (up to ∼10-fold) after cross-linking by UV irradiation at room temperature, compared with un-cross-linked microfiber scaffolds. The preservation of stiffness and high average fiber modulus (370 ± 166 MPa) within the cross-linked hydrated scaffolds upon repetitive loading (10% strain at 1 Hz up to 200,000 cycles) suggests that the prepared scaffolds may be of potential interest for soft connective tissue engineering applications. Moreover, the approach can be readily adapted through manipulation of polymer properties and scaffold geometry to prepare structures with mechanical properties suitable for other tissue engineering applications.
authors.forename: Fei
authors.initials: F
authors.lastname: Chen
authors.affiliation: Department of Functional Materials in Medicine and Dentistry, University of Würzburg , 97070 Würzburg, Germany.
authors.forename: Gernot
authors.initials: G
authors.lastname: Hochleitner
authors.affiliation: Christchurch Regenerative Medicine and Tissue Engineering Group, Department of Orthopaedic Surgery, Centre for Bioengineering & Nanomedicine, University of Otago Christchurch , Christchurch 8140, New Zealand.
authors.forename: Tim
authors.initials: T
authors.lastname: Woodfield
authors.affiliation: Department of Functional Materials in Medicine and Dentistry, University of Würzburg , 97070 Würzburg, Germany.
authors.forename: Juergen
authors.initials: J
authors.lastname: Groll
authors.affiliation: Department of Functional Materials in Medicine and Dentistry, University of Würzburg , 97070 Würzburg, Germany.
authors.forename: Paul D
authors.initials: PD
authors.lastname: Dalton
authors.forename: Brian G
authors.initials: BG
authors.lastname: Amsden
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D063566:Biodegradable Plastics / Q000737:chemistry*; D003238:Connective Tissue / Q000502:physiology*; D011091:Polyesters / Q000737:chemistry; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry; D066330:Printing, Three-Dimensional; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D063566:Biodegradable Plastics; D011091:Polyesters; D011108:Polymers; C016240:polycaprolactone