title: Uniformly-dispersed nanohydroxapatite-reinforced poly(ε-caprolactone) composite films for tendon tissue engineering application.
abstract: Regeneration of injuries at tendon-to-bone interface (TBI) remains a challenging issue due to the complex tissue composition involving both soft tendon tissues and relatively hard bone tissues. Tissue engineering using polymeric/ceramic composites has been of great interest to generate scaffolds for tissue's healing at TBI. Herein, we presented a novel method to blend polymers and bioceramics for tendon tissue engineering application. A homogeneous composite comprising of nanohydroxyapatite (nHA) particles in poly(ε-caprolactone) (PCL) matrix was obtained using a combination of solvent and mechanical blending process. X-ray diffraction analysis showed that the as-fabricated PCL/nHA composite film retained phase-pure apatite and semi-crystalline properties of PCL. Infrared spectroscopy spectra confirmed that the PCL/nHA composite film exhibited the characteristics functional groups of PCL and nHA, without alteration to the chemical properties of the composite. The incorporation of nHA resulted in PCL/nHA composite film with improved mechanical properties such as Young's Modulus and ultimate tensile stress, which were comparable to that of the native human rotator tendon. Seeding with human tenocytes, cells attached on the PCL/nHA composite film, and after 14days of culturing, these cells could acquire elongated morphology without induced cytotoxicity. PCL/nHA composite film could also result in increased cell metabolism with prolonged culturing, which was comparable to that of the PCL group and higher than that of the nHA group. All these results demonstrated that the developed technique of combining solvent and mechanical blending could be applied to fabricate composite films with potential for tendon tissue engineering applications.
authors: Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117 576, Singapore.
authors: Shi Yun
authors: SY
authors: Tong
authors: Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117 576, Singapore. Electronic address: zuyong.nus@gmail.com.
authors: Zuyong
authors: Z
authors: Wang
authors: Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117 576, Singapore.
authors: Poon Nian
authors: PN
authors: Lim
authors: Department of Orthopaedic Surgery, National University of Singapore, 5 Lower Kent Ridge Road, Singapore 119 074, Singapore.
authors: Wilson
authors: W
authors: Wang
authors: Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117 576, Singapore. Electronic address: mpetes@nus.edu.sg.
authors: Eng San
authors: ES
authors: Thian
mesh_terms: D002448:Cell Adhesion / Q000187:drug effects; D017886:Durapatite / Q000737:chemistry* / Q000494:pharmacology; D006801:Humans; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D011091:Polyesters / Q000737:chemistry / Q000494:pharmacology*; D017550:Spectroscopy, Fourier Transform Infrared; D013710:Tendons / Q000187:drug effects / Q000502:physiology*; D000070916:Tenocytes / Q000166:cytology / Q000187:drug effects / Q000648:ultrastructure; D013718:Tensile Strength / Q000187:drug effects; D023822:Tissue Engineering / Q000379:methods*; D014961:X-Ray Diffraction
chemical_list: D011091:Polyesters; C016240:polycaprolactone; D017886:Durapatite
keywords: Hydroxyapatite; Poly(ε-caprolactone); Tendon tissue engineering; Tendon-to-bone interface