title: Two-dimensional nanoscale structural and functional imaging in individual collagen type I fibrils.
abstract: The piezoelectric properties of single collagen type I fibrils in fascia were imaged with sub-20 nm spatial resolution using piezoresponse force microscopy. A detailed analysis of the piezoresponse force microscopy signal in controlled tip-fibril geometry revealed shear piezoelectricity parallel to the fibril axis. The direction of the displacement is preserved along the whole fiber length and is independent of the fiber conformation. It is shown that individual fibrils within bundles in skeletal muscle fascia can have opposite polar orientations and are organized into domains, i.e., groups of several fibers having the same polar orientation. We were also able to detect piezoelectric activity of collagen fibrils in the high-frequency range up to 200 kHz, suggesting that the mechanical response time of biomolecules to electrical stimuli can be approximately 5 micros.
authors.affiliation: Institut National de la Recherche Scientifique, Centre Energie, Matériaux et Télécommunications, Varennes, Québec, Canada.
authors.forename: Catalin
authors.initials: C
authors.lastname: Harnagea
authors.forename: Martin
authors.initials: M
authors.lastname: Vallières
authors.forename: Christian P
authors.initials: CP
authors.lastname: Pfeffer
authors.forename: Dong
authors.initials: D
authors.lastname: Wu
authors.forename: Bjorn R
authors.initials: BR
authors.lastname: Olsen
authors.forename: Alain
authors.initials: A
authors.lastname: Pignolet
authors.forename: François
authors.initials: F
authors.lastname: Légaré
authors.forename: Alexei
authors.initials: A
authors.lastname: Gruverman
mesh_terms: D000818:Animals; D016880:Anisotropy; D001696:Biomechanical Phenomena; D024042:Collagen Type I / Q000737:chemistry / Q000378:metabolism* / Q000648:ultrastructure*; D004560:Electricity; D051379:Mice; D018625:Microscopy, Atomic Force; D008958:Models, Molecular; D057054:Molecular Imaging; D036103:Nanotechnology; D017434:Protein Structure, Tertiary; D013997:Time Factors
chemical_list: D024042:Collagen Type I