title: A mechanical evaluation of micro-HA/CS composite scaffolds with interconnected spherical macropores.
abstract: BACKGROUND
  In the process of bone defective reparation and engineered bone tissue construction, osteoblasts are adhered to the surface of the scaffold materials and impart the external mechanical load to the osteoblasts. So, the dynamic mechanical property of the scaffolds play an important role in the bone tissue repair and it is valuable to research. Material type and the architectural design of scaffolds are also important to facilitate cell and tissue growth. The aim of this study was to prepare a kind of material with good pore connectivity and analyze its dynamic mechanical property.
  
  
  METHODS
  Fabrication and characterization of micro-hydroxyapatite(m-HA)/chitosan(CS) polymer composite scaffolds with well interconnected spherical pore architectures were reports. Micro-HA was prepared by being calcined and ball milled. Paraffin spheres in the range of 160-330 µm were fabricated with a dispersion method and used as the porogen in the fabrication of the scaffolds. Polymer scaffolds were fabricated by the technique of compression molding and particulate leaching method. The effects of the porogen content on the properties of the scaffolds were studied.
  
  
  RESULTS
  With the increase of porogen, the pore of the scaffolds increased and became interconnected. Cyclic loading of three scaffolds were tested with 10 % strain under four levels of loading frequency, 0.1, 0.5, 1 and 1.5 Hz. The porous composite scaffolds exhibited a viscosity-elastic behaviour with a maximum stress of 3-4 kPa. At each frequency, modulus value is decreased with the paraffin microspheres content, but there was no significance difference in the peak stress of the three samples. All the samples tested displayed clear hysteresis loops. There was no significance difference in the peak hysteresis of the three samples, and the hysteresis difference values between the sixth compression cycle and the initial cycle for three samples was similar, with no statistically significant differences.
  
  
  CONCLUSIONS
  Micro-HA/CS composite scaffolds with interconnected spherical macropores were fabricated using pherical paraffin as porogen. The porous composite scaffolds exhibited a viscosity-elastic behaviour with good repeatability. It is benefit to study the influence of the mechanical load on the cell of the scaffold.
authors.affiliation: Institute of Medical Equipment, The Academy of Military Medical Sciences, Tianjin, 300161, China. limxinxin@163.com.
authors.forename: Li
authors.initials: L
authors.lastname: Ruixin
authors.affiliation: Institute of Medical Equipment, The Academy of Military Medical Sciences, Tianjin, 300161, China. lidong19900117@163.com.|Tianjin Medical University, Qi Xiangtai Road No. 22, Heping District, Tianjin, 300070, China. lidong19900117@163.com.
authors.forename: Li
authors.initials: L
authors.lastname: Dong
authors.affiliation: Institute of Medical Equipment, The Academy of Military Medical Sciences, Tianjin, 300161, China. 994603837@qq.com.|NO.1 Hospital of Jilin University, Xinmin District, Changchun, Jinlin, 130000, China. 994603837@qq.com.
authors.forename: Zhao
authors.initials: Z
authors.lastname: Bin
authors.affiliation: Institute of Medical Equipment, The Academy of Military Medical Sciences, Tianjin, 300161, China. llihao2006011653@sina.com.
authors.forename: Li
authors.initials: L
authors.lastname: Hao
authors.affiliation: Institute of Medical Equipment, The Academy of Military Medical Sciences, Tianjin, 300161, China. lengda767@163.com.
authors.forename: Leng
authors.initials: L
authors.lastname: Xue
authors.affiliation: Institute of Medical Equipment, The Academy of Military Medical Sciences, Tianjin, 300161, China. 759527727@qq.com.
authors.forename: Shi
authors.initials: S
authors.lastname: Caihong
authors.affiliation: Institute of Medical Equipment, The Academy of Military Medical Sciences, Tianjin, 300161, China. 13512062095@126.com.
authors.forename: Su
authors.initials: S
authors.lastname: Weihua
authors.affiliation: Institute of Medical Equipment, The Academy of Military Medical Sciences, Tianjin, 300161, China. qinxl_0704@126.com.
authors.forename: Qin
authors.initials: Q
authors.lastname: Xiaoli
authors.affiliation: Institute of Medical Equipment, The Academy of Military Medical Sciences, Tianjin, 300161, China. yuanyinghainku@126.com.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Yinghai
authors.affiliation: Institute of Medical Equipment, The Academy of Military Medical Sciences, Tianjin, 300161, China. asdawnasd@163.com.
authors.forename: An
authors.initials: A
authors.lastname: Weining
authors.affiliation: Institute of Medical Equipment, The Academy of Military Medical Sciences, Tianjin, 300161, China. z84656716@yahoo.com.
authors.forename: Zhang
authors.initials: Z
authors.lastname: Xizheng
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D048271:Chitosan / Q000737:chemistry*; D017886:Durapatite / Q000737:chemistry*; D055595:Mechanical Phenomena; D010232:Paraffin / Q000737:chemistry; D010316:Particle Size; D016062:Porosity; D054457:Tissue Scaffolds / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D001672:Biocompatible Materials; D014867:Water; D010232:Paraffin; D048271:Chitosan; D017886:Durapatite
references.citation: Biomaterials. 2000 Dec;21(24):2589-98
references.pmid: 11071608
references.citation: Tissue Eng. 2001 Feb;7(1):23-33
references.pmid: 11224921
references.citation: J Biomed Mater Res. 2001 Apr;55(1):20-7
references.pmid: 11426393
references.citation: Biomaterials. 2002 Nov;23(21):4167-76
references.pmid: 12194519
references.citation: Biomaterials. 2003 Jun;24(13):2161-75
references.pmid: 12699652
references.citation: Biomaterials. 2003 Jun;24(13):2339-49
references.pmid: 12699672
references.citation: Biomaterials. 2004 May;25(11):2065-73
references.pmid: 14741621
references.citation: Biomaterials. 2004 Nov;25(24):5507-14
references.pmid: 15142732
references.citation: Biomaterials. 2004 Dec;25(27):5821-30
references.pmid: 15172494
references.citation: Ann N Y Acad Sci. 1988;523:131-6
references.pmid: 3289449
references.citation: Science. 1993 May 14;260(5110):920-6
references.pmid: 8493529
references.citation: Clin Mater. 1994;15(4):267-72
references.pmid: 10147170
references.citation: J Biomech. 1997 Jul;30(7):743-5
references.pmid: 9239556
references.citation: Biomaterials. 1999 Jun;20(12):1133-42
references.pmid: 10382829
references.citation: Chem Rev. 2004 Dec;104(12):6017-84
references.pmid: 15584695
references.citation: Bone. 2008 Feb;42(2):432-8
references.pmid: 18032124
references.citation: J Mech Behav Biomed Mater. 2009 Apr;2(2):138-46
references.pmid: 19627817
references.citation: Colloids Surf B Biointerfaces. 2009 Nov 1;74(1):159-66
references.pmid: 19679453
references.citation: Acta Biomater. 2010 Mar;6(3):856-63
references.pmid: 19665061
references.citation: Acta Biomater. 2010 Jun;6(6):2020-7
references.pmid: 20004748