title: Manufacture of multimicrotubule chitosan nerve conduits with novel molds and characterization in vitro.
abstract: Multimicrotubule chitosan conduits (M-conduits) were fabricated using novel molds and a thermal-induced phase-separation technique. Hollow chitosan conduits (H-conduits) with an inner diameter of 1-5 mm and a wall thickness of 0.2-1.0 mm were made, and then a novel mold composed of a styrofoam insulating pedestal with several holes and a stainless steel cover plate was used to make M-conduits. In brief, corresponding H-conduits were inserted upright into the holes of the styrofoam pedestal, and filled with chitosan solution, then rapidly covered with the precooled stainless steel cover plate, and then placed in a freezer. The styrofoam insulating pedestal enclosing the conduits could reduce the heat transfer through the side wall of the conduits. Gradual phase separation then occurred uniaxially in the presence of a unidirectional temperature gradient from the top end to the bottom end of the chitosan conduits. The phase-separated polymer/solvent systems were then dried in a freeze-dryer. The microtubule diameters were controlled by adjusting the polymer concentration and cooling temperature. In vitro characterization demonstrated that the mold-based multimicrotubule chitosan conduits possessed suitable mechanical strength, microtubule diameter distribution, porosity, swelling, biodegradability, and nerve cell affinity, and so they showed potential for application as nerve tissue engineering scaffolds.
authors.affiliation: Department of Biological Sciences and Biotechnology, State Key Laboratory of Biomembrane and Membrane Biotechnology, Tsinghua University, Beijing 100084, People's Republic of China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Ao
authors.forename: Aijun
authors.initials: A
authors.lastname: Wang
authors.forename: Wenling
authors.initials: W
authors.lastname: Cao
authors.forename: Ling
authors.initials: L
authors.lastname: Zhang
authors.forename: Lijun
authors.initials: L
authors.lastname: Kong
authors.forename: Qing
authors.initials: Q
authors.lastname: He
authors.forename: Yandao
authors.initials: Y
authors.lastname: Gong
authors.forename: Xiufang
authors.initials: X
authors.lastname: Zhang
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D001672:Biocompatible Materials / Q000138:chemical synthesis* / Q000378:metabolism; D002460:Cell Line; D048271:Chitosan / Q000737:chemistry* / Q000378:metabolism; D048091:Guided Tissue Regeneration / Q000379:methods; D008422:Materials Testing; D051379:Mice; D009416:Nerve Regeneration; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D016062:Porosity; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D001672:Biocompatible Materials; D048271:Chitosan