title: Manufacture of layered collagen/chitosan-polycaprolactone scaffolds with biomimetic microarchitecture.
abstract: Chitosan-polycaprolactone (CH-PCL) copolymers with various PCL percentages less than 45 wt% were synthesized. Different CH-PCLs were respectively blended with Type-II collagen at prescribed ratios to fabricate a type of layered porous scaffolds with some biomimetic features while using sodium tripolyphosphate as a crosslinker. The compositions of different layers inside scaffolds were designed in a way so that from the top layer to the bottom layer collagen content changed in a degressive trend contrary to that of chitosan. A combinatorial processing technique involving adjustable temperature gradients, collimated photothermal heating and freeze-drying was used to construct desired microstructures of scaffolds. The resultant scaffolds had highly interconnected porous layers with a layer thickness of around 1mm and porous interface zones without visual clefts. Results obtained from SEM observations and measurements of pore parameters and swelling properties as well as mechanical examinations confirmed that graded average pore-size and porosity, gradient swelling index and oriented compressive modulus for certain scaffolds were synchronously achieved. In addition, certain evaluations of cell-scaffold constructs indicated that the achieved scaffolds were able to well support the growth of seeded chondrocytes. The optimized collagen/CH-PCL scaffolds are partially similar to articular cartilage extracellular matrix in composition, porous microarchitecture, water content and compressive mechanical properties, suggesting that they have promising potential for applications in articular cartilage repair.
authors.affiliation: Department of Stomatology, Zhongnan Hospital, Wuhan University, 430071, PR China.
authors.forename: Youjia
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, PR China. Electronic address: ying_x_wan@yahoo.ca.
authors.forename: Ying
authors.initials: Y
authors.lastname: Wan
authors.affiliation: Department of Chemistry and Chemical Engineering, Royal Military College of Canada, Kingston, Ontario, Canada K7K 7B4.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.affiliation: College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, PR China.
authors.forename: Dengke
authors.initials: D
authors.lastname: Yin
authors.affiliation: College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, PR China.
authors.forename: Wenze
authors.initials: W
authors.lastname: Cheng
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D032701:Biomimetics / Q000379:methods*; D048271:Chitosan / Q000737:chemistry*; D003094:Collagen / Q000737:chemistry*; D011091:Polyesters / Q000737:chemistry*; D016062:Porosity; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D011091:Polyesters; C016240:polycaprolactone; D003094:Collagen; D048271:Chitosan
keywords: Articular cartilage matrix; Biomimetic scaffold; Chitosan-polycaprolactone copolymer; Collagen; Combinatorial processing technique