In situ tensile testing of human aortas by time-resolved small-angle X-ray scattering.
The collagen diffraction patterns of human aortas under uniaxial tensile test conditions have been investigated by synchrotron small-angle X-ray scattering. Using a recently designed tensile testing device the orientation and d-spacing of the collagen fibers in the adventitial layer have been measured in situ with the macroscopic force and sample stretching under physiological conditions. The results show a direct relation between the orientation and extension of the collagen fibers on the nanoscopic level and the macroscopic stress and strain. This is attributed first to a straightening, second to a reorientation of the collagen fibers, and third to an uptake of the increasing loads by the collagen fibers.
Schmid
F
F
Austrian Academy of Science, Institute of Biophysics and X-ray Structure Research, Graz, Austria.
Sommer
G
G
Rappolt
M
M
Schulze-Bauer
C A J
CA
Regitnig
P
P
Holzapfel
G A
GA
Laggner
P
P
Amenitsch
H
H
D001011:Aorta / Q000737:chemistry / Q000502:physiology*; D001696:Biomechanical Phenomena; D003094:Collagen / Q000737:chemistry / Q000502:physiology*; D004548:Elasticity; D006801:Humans; D012542:Scattering, Radiation; D017356:Synchrotrons; D013718:Tensile Strength; D014961:X-Ray Diffraction / Q000295:instrumentation / Q000379:methods*
D003094:Collagen