title: Comparison between PCL/hydroxyapatite (HA) and PCL/halloysite nanotube (HNT) composite scaffolds prepared by co-extrusion and gas foaming.
abstract: In this work, three-dimensional poly(caprolactone) (PCL) tissue engineering scaffolds were prepared by co-extrusion and gas foaming. Biocompatible hydroxyapatite (HA) and halloysite nanotubes (HNT) were added to the polymer matrix to enhance the mechanical properties and bioactivity of the composite scaffolds. The effects of HA and HNT on the rheological behavior, microstructure, and mechanical properties of the composite scaffolds were systematically compared. It was found that the HNT improved viscosity more significantly than HA, and reduced the pore size of scaffolds, while the mechanical performance of PCL/HNT scaffolds was higher than PCL/HA scaffolds with the same filler content. Human mesenchymal stem cells (hMSCs) were used as the cell model to compare the biological properties of two composite scaffolds. The results demonstrated that cells could survive on all scaffolds, and showed a more flourishing living state on the composite scaffolds. The cell differentiation for 5% HA and 1% HNT scaffolds were significantly higher than other scaffolds, while the differentiation of 5% HNT scaffolds was lower than that of 1% HNT scaffolds mainly because of the reduced pore size and pore interconnectivity. Therefore, this study suggested that, with proper filler content and control of microstructure through processing, HNT could be a suitable substitute for HA for bone tissue engineering to reduce the cost and improve mechanical performance.
authors.affiliation: The Key Laboratory for Polymer Processing Engineering of Ministry of Education, South China University of Technology, Guangzhou 510640, China; Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI 53715, United States.
authors.forename: Xin
authors.initials: X
authors.lastname: Jing
authors.affiliation: The Key Laboratory for Polymer Processing Engineering of Ministry of Education, South China University of Technology, Guangzhou 510640, China; Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI 53715, United States. Electronic address: mehymi@scut.edu.
authors.forename: Hao-Yang
authors.initials: HY
authors.lastname: Mi
authors.affiliation: Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI 53715, United States; Department of Mechanical Engineering, University of Wisconsin-Madison, Madison, WI 53715, United States. Electronic address: turng@engr.wisc.edu.
authors.forename: Lih-Sheng
authors.initials: LS
authors.lastname: Turng
mesh_terms: D000538:Aluminum Silicates / Q000737:chemistry*; D001672:Biocompatible Materials / Q000737:chemistry / Q000494:pharmacology; D001861:Bone Regeneration / Q000187:drug effects; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D000077215:Clay; D019245:Compressive Strength; D003599:Cytoskeleton / Q000187:drug effects; D017886:Durapatite / Q000737:chemistry*; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D043942:Nanotubes / Q000737:chemistry*; D011091:Polyesters / Q000737:chemistry*; D016062:Porosity; D012212:Rheology; D013818:Thermogravimetry; D023822:Tissue Engineering; D054457:Tissue Scaffolds; D014961:X-Ray Diffraction
chemical_list: D000538:Aluminum Silicates; D001672:Biocompatible Materials; D011091:Polyesters; C016240:polycaprolactone; D017886:Durapatite; D000077215:Clay
keywords: Bone tissue engineering; Extrusion foaming; Halloysite nanotube; Hydroxyapatite; Poly(caprolactone)