title: Micro-computed tomographical imaging of soft biological materials using contrast techniques.
abstract: The aim of this work was to introduce high-resolution computed tomography (micro-CT) for scaffolds made from soft natural biomaterials, and to compare these data with the conventional techniques scanning electron microscopy and light microscopy. Collagen-based scaffolds were used as examples. Unlike mineralized tissues, collagen scaffolds do not provide enough X-ray attenuation for micro-CT imaging. Therefore, various metal-based contrast agents were applied and evaluated using two structurally distinct scaffolds, one with round pores and one with unidirectional lamellae. The optimal contrast techniques for obtaining high-resolution three-dimensional images were either a combination of osmium tetroxide and uranyl acetate, or a combination of uranyl acetate and lead citrate. The data obtained by micro-CT analysis were in line with data obtained by light and electron microscopy. However, small structures (less than a few mum) could not be visualized due to limitation of the spot size of the micro-CT apparatus. In conclusion, reliable three-dimensional images of scaffolds prepared from soft natural biomaterials can be obtained using appropriate contrast protocols. This extends the use of micro-CT analysis to soft materials, such as protein-based biomaterials.
authors.affiliation: Department of Biochemistry 280, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, 6500 HB Nijmegen, The Netherlands.
authors.forename: Kaeuis A
authors.initials: KA
authors.lastname: Faraj
authors.forename: Vincent M J I
authors.initials: VM
authors.lastname: Cuijpers
authors.forename: Ronnie G
authors.initials: RG
authors.lastname: Wismans
authors.forename: X Frank
authors.initials: XF
authors.lastname: Walboomers
authors.forename: John A
authors.initials: JA
authors.lastname: Jansen
authors.forename: Toin H
authors.initials: TH
authors.lastname: van Kuppevelt
authors.forename: Willeke F
authors.initials: WF
authors.lastname: Daamen
mesh_terms: D001672:Biocompatible Materials / Q000032:analysis / Q000737:chemistry*; D040761:Biomimetic Materials / Q000032:analysis / Q000737:chemistry*; D003287:Contrast Media; D005109:Extracellular Matrix / Q000000981:diagnostic imaging*; D008422:Materials Testing / Q000379:methods; D011856:Radiographic Image Enhancement / Q000379:methods*; D012031:Refractometry / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D001672:Biocompatible Materials; D003287:Contrast Media