title: Synchrotron X-ray nanomechanical imaging of mineralized fiber composites.
abstract: In situ synchrotron X-ray scattering and diffraction, in combination with micromechanical testing, can provide quantitative information on the nanoscale mechanics of biomineralized composites, such as bone, nacre, and enamel. Due to the hierarchical architecture of these systems, the methodology for extraction of mechanical parameters at the molecular and supramolecular scale requires special considerations regarding design of mechanical test apparatus, sample preparation and testing, data analysis, and interpretation of X-ray structural information in terms of small-scale mechanics. In this chapter, this methodology is described using as a case study the deformation mechanisms at the fibrillar and mineral particle level in cortical bone. Following a description of the sample preparation, testing, and analysis procedures for bone in general, two applications of the method-to understand fibrillar-level mechanics in tension and bending in a mouse model of rachitic disease-are presented, together with a discussion of how to relate in situ scattering and diffraction data acquired during mechanical testing to nanostructural models for deformation of biomineralized composites.
authors.affiliation: Queen Mary University of London, School of Engineering and Material Sciences, London, United Kingdom.
authors.forename: Angelo
authors.initials: A
authors.lastname: Karunaratne
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Terrill
authors.forename: Himadri S
authors.initials: HS
authors.lastname: Gupta
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D005269:Femur / Q000502:physiology / Q000648:ultrastructure; D024022:Fibrillar Collagens / Q000648:ultrastructure*; D051379:Mice; D053761:Nanocomposites / Q000648:ultrastructure; D057139:Nanofibers / Q000648:ultrastructure; D016062:Porosity; D053838:Scattering, Small Angle; D017356:Synchrotrons; D013718:Tensile Strength; D014961:X-Ray Diffraction
chemical_list: D024022:Fibrillar Collagens
keywords: Bone matrix properties; In situ synchrotron microprobe techniques; Mineralized collagen fibril; Nanomechanical imaging; Nanoscale models of deformation; Small-angle X-ray scattering; Wide-angle X-ray diffraction