title: Evaluation of biodegradable elastic scaffolds made of anionic polyurethane for cartilage tissue engineering.
abstract: Biodegradable polyurethane (PU) was synthesized by a water-based process. The process rendered homogenous PU nanoparticles (NPs). Spongy PU scaffolds in large dimensions were obtained by freeze-drying the PU NP dispersion. The spongy scaffolds were characterized in terms of the porous structure, wettability, mechanical properties, degradation behavior, and degradation products. The capacity as cartilage tissue engineering scaffolds was evaluated by growing chondrocytes and mesenchymal stem cells (MSCs) in the scaffolds. Scaffolds made from the PU dispersion had excellent hydrophilicity, porosity, and water absorption. Examination by micro-computed tomography confirmed that PU scaffolds had good pore interconnectivity. The degradation rate of the scaffolds in phosphate buffered saline was much faster than that in papain solution or in deionized water at 37°C. The biodegradable PU appeared to be degraded via the cleavage of ester linkage The intrinsic elastic property of PU and the gyroid-shape porous structure of the scaffolds may have accounted for the outstanding strain recovery (87%) and elongation behavior (257%) of the PU scaffolds, compared to conventional poly(d,l-lactide) (PLA) scaffolds. Chondrocytes were effectively seeded in PU scaffolds without pre-wetting. They grew better and secreted more glycosaminoglycan in PU scaffolds vs. PLA scaffolds. Human MSCs showed greater chondrogenic gene expression in PU scaffolds than in PLA scaffolds after induction. Based on the favorable hydrophilicity, elasticity, and regeneration capacities, the novel biodegradable PU scaffolds may be superior to the conventional biodegradable scaffolds in cartilage tissue engineering applications.
authors.affiliation: Institute of Polymer Science and Engineering, National Taiwan University, Taipei, Taiwan.
authors.forename: Meng-Chao
authors.initials: MC
authors.lastname: Tsai
authors.affiliation: Institute of Polymer Science and Engineering, National Taiwan University, Taipei, Taiwan.
authors.forename: Kun-Che
authors.initials: KC
authors.lastname: Hung
authors.affiliation: Institute of Clinical Medicine and Institute of Pharmacology, Faculty of Medicine, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Shih-Chieh
authors.initials: SC
authors.lastname: Hung
authors.affiliation: Institute of Polymer Science and Engineering, National Taiwan University, Taipei, Taiwan. Electronic address: shhsu@ntu.edu.tw.
authors.forename: Shan-hui
authors.initials: SH
authors.lastname: Hsu
mesh_terms: D000838:Anions; D001672:Biocompatible Materials / Q000737:chemistry / Q000494:pharmacology*; D015415:Biomarkers / Q000378:metabolism; D002356:Cartilage / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects; D019902:Chondrocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D006025:Glycosaminoglycans / Q000096:biosynthesis / Q000378:metabolism; D006801:Humans; D006868:Hydrolysis; D057927:Hydrophobic and Hydrophilic Interactions; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D011091:Polyesters / Q000737:chemistry / Q000494:pharmacology; D011140:Polyurethanes / Q000737:chemistry / Q000494:pharmacology*; D016062:Porosity; D061251:Primary Cell Culture; D023822:Tissue Engineering; D054457:Tissue Scaffolds; D017155:Wettability; D055114:X-Ray Microtomography
chemical_list: D000838:Anions; D001672:Biocompatible Materials; D015415:Biomarkers; D006025:Glycosaminoglycans; D011091:Polyesters; D011140:Polyurethanes; C033616:poly(lactide)
keywords: Biodegradable polyurethane; Cartilage; Degradation; Elasticity; Scaffold