title: Effect of negatively charged cellulose nanofibers on the dispersion of hydroxyapatite nanoparticles for scaffolds in bone tissue engineering.
abstract: Nanofibrous 2,2,6,6-tetramethylpiperidine-1-oxyl(TEMPO)-oxidized bacterial cellulose (TOBC) was used as a dispersant of hydroxyapatite (HA) nanoparticles in aqueous solution. The surfaces of TOBC nanofibers were negatively charged after the reaction with the TEMPO/NaBr/NaClO system at pH 10 and room temperature. HA nanoparticles were simply adsorbed on the TOBC nanofibers (HA-TOBC) and dispersed well in DI water. The well-dispersed HA-TOBC colloidal solution formed a hydrogel after the addition of gelatin, followed by crosslinking with glutaraldehyde (HA-TOBC-Gel). The chemical modification of the fiber surfaces and the colloidal stability of the dispersion solution confirmed TOBC as a promising HA dispersant. Both the Young's modulus and maximum tensile stress increased as the amount of gelatin increased due to the increased crosslinking of gelatin. In addition, the well-dispersed HA produced a denser scaffold structure resulting in the increase of the Young's modulus and maximum tensile stress. The well-developed porous structures of the HA-TOBC-Gel composites were incubated with Calvarial osteoblasts. The HA-TOBC-Gel significantly improved cell proliferation as well as cell differentiation confirming the material as a potential candidate for use in bone tissue engineering scaffolds.
authors.affiliation: Department of Biosystems and Biomaterials Science and Engineering, Seoul National University, Seoul 151-921, Republic of Korea.
authors.forename: Minsung
authors.initials: M
authors.lastname: Park
authors.affiliation: Department of Biosystems and Biomaterials Science and Engineering, Seoul National University, Seoul 151-921, Republic of Korea.
authors.forename: Dajung
authors.initials: D
authors.lastname: Lee
authors.affiliation: Department of Biosystems and Biomaterials Science and Engineering, Seoul National University, Seoul 151-921, Republic of Korea.
authors.forename: Sungchul
authors.initials: S
authors.lastname: Shin
authors.affiliation: Department of Biosystems and Biomaterials Science and Engineering, Seoul National University, Seoul 151-921, Republic of Korea; Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea; Center for Food and Bioconvergence, Seoul National University, Seoul 151-921, Republic of Korea. Electronic address: jhyun@snu.ac.kr.
authors.forename: Jinho
authors.initials: J
authors.lastname: Hyun
mesh_terms: D000327:Adsorption; D000818:Animals; D000831:Animals, Newborn; D001672:Biocompatible Materials / Q000737:chemistry / Q000494:pharmacology; D001842:Bone and Bones / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D049109:Cell Proliferation / Q000187:drug effects; D002482:Cellulose / Q000737:chemistry*; D003497:Cyclic N-Oxides / Q000737:chemistry; D017886:Durapatite / Q000737:chemistry*; D055119:Elastic Modulus; D020100:Hydrogels / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D057139:Nanofibers / Q000737:chemistry* / Q000648:ultrastructure; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D010012:Osteogenesis / Q000502:physiology; D016062:Porosity; D017207:Rats, Sprague-Dawley; D013718:Tensile Strength; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D003497:Cyclic N-Oxides; D020100:Hydrogels; D002482:Cellulose; D017886:Durapatite; C003959:TEMPO
keywords: Bacterial cellulose; Colloidal stability; Dispersant; Hydroxyapatite; Scaffold