title: Open-Source Selective Laser Sintering (OpenSLS) of Nylon and Biocompatible Polycaprolactone.
abstract: Selective Laser Sintering (SLS) is an additive manufacturing process that uses a laser to fuse powdered starting materials into solid 3D structures. Despite the potential for fabrication of complex, high-resolution structures with SLS using diverse starting materials (including biomaterials), prohibitive costs of commercial SLS systems have hindered the wide adoption of this technology in the scientific community. Here, we developed a low-cost, open-source SLS system (OpenSLS) and demonstrated its capacity to fabricate structures in nylon with sub-millimeter features and overhanging regions. Subsequently, we demonstrated fabrication of polycaprolactone (PCL) into macroporous structures such as a diamond lattice. Widespread interest in using PCL for bone tissue engineering suggests that PCL lattices are relevant model scaffold geometries for engineering bone. SLS of materials with large powder grain size (~500 μm) leads to part surfaces with high roughness, so we further introduced a simple vapor-smoothing technique to reduce the surface roughness of sintered PCL structures which further improves their elastic modulus and yield stress. Vapor-smoothed PCL can also be used for sacrificial templating of perfusable fluidic networks within orthogonal materials such as poly(dimethylsiloxane) silicone. Finally, we demonstrated that human mesenchymal stem cells were able to adhere, survive, and differentiate down an osteogenic lineage on sintered and smoothed PCL surfaces, suggesting that OpenSLS has the potential to produce PCL scaffolds useful for cell studies. OpenSLS provides the scientific community with an accessible platform for the study of laser sintering and the fabrication of complex geometries in diverse materials.
authors: Department of Bioengineering, Rice University, Houston, Texas, United States of America.
authors: Ian S
authors: IS
authors: Kinstlinger
authors: Department of Bioengineering, Rice University, Houston, Texas, United States of America.
authors: Andreas
authors: A
authors: Bastian
authors: Department of Bioengineering, Rice University, Houston, Texas, United States of America.
authors: Samantha J
authors: SJ
authors: Paulsen
authors: Department of Bioengineering, Rice University, Houston, Texas, United States of America.
authors: Daniel H
authors: DH
authors: Hwang
authors: Department of Bioengineering, Rice University, Houston, Texas, United States of America.
authors: Anderson H
authors: AH
authors: Ta
authors: Department of Bioengineering, Rice University, Houston, Texas, United States of America.
authors: David R
authors: DR
authors: Yalacki
authors: Lansing Makers Network, Lansing, Michigan, United States of America.
authors: Tim
authors: T
authors: Schmidt
authors: Department of Bioengineering, Rice University, Houston, Texas, United States of America.
authors: Jordan S
authors: JS
authors: Miller
mesh_terms: D001672:Biocompatible Materials / Q000138:chemical synthesis*; D001842:Bone and Bones / Q000601:surgery; D002448:Cell Adhesion / Q000502:physiology; D002454:Cell Differentiation / Q000502:physiology; D002470:Cell Survival / Q000502:physiology; D002478:Cells, Cultured; D055119:Elastic Modulus; D006801:Humans; D007834:Lasers; D008422:Materials Testing; D059630:Mesenchymal Stem Cells / Q000502:physiology*; D009757:Nylons / Q000737:chemistry*; D011091:Polyesters / Q000737:chemistry*; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds
chemical_list: D001672:Biocompatible Materials; D009757:Nylons; D011091:Polyesters; C016240:polycaprolactone