Assistant Professor Ohio University, United States
Introduction:: 3D printing of biomaterial scaffolds offers chances to revolutionize tissue engineering and clinical medicine, provided that sufficient materials can be developed. The material design includes both polymer composition as well as scaffold morphology and lifespan of the device in vivo. Polymer foams and printed porous scaffolds are promising classes of biomaterial, as the porosity and tunable physical properties are often better matches for native tissue compared with solid polymer analogs.
Materials and Methods:: A combination of processing techniques (3D printing, electrospinning, etc) have been examined as a means of producing porous tissue scaffolds, with porosity introduced across multiple length scales (nano/micro to macroscopic). The reproducibility of the pores relative to the technique, and the resultant physical properties are characterized using a variety of standard methods. In vitro and in vivo analysis is then used to validate the scaffold design and assess both biocompatibility as well as long-term behavior of the scaffolds.
Results, Conclusions, and Discussions:: Polymer thermosets produced by “click” reactions, including thiol-ene and thiol-epoxy crosslinking, are capable of being into scaffolds and foams where physical properties and morphologies may be tailored through a combination of chemical composition and physical processing methods. Compositional selection may further be used to introduce feedback mechanisms into the scaffold design. Ultimately this provides a means of tailoring scaffold performance from printer-to-host. Direct ink writing of thiol-epoxy/thiol-ene click foams is compared with more conventional but less robust filament deposition modeling of foamed poly(lactic acid) filaments. The cellular risks and cytocompatibility are demonstrated across multiple cell lines. Subcutaneous murine implantation studies over 8 weeks are used to probe biocompatibility, host-implant response, and degradation behavior in vivo.
