Abstract
Abstract. To better understand the function of the components in the multi-hierarchical structure of connective tissue, it is necessary to observe it at different scale levels.
The basic building element, type I collagen, is a great harmonophore that generates second harmonic signal. This two-photon label-free microscopy can be combined with the material tensile test.
Together with the change of the polarization plane of incident beam, it is possible to yield the information about the collagen helical pitch angle. These methods reveal some material features from nano to macro state.
In this case a rabbit Achilles tendon was deformed and simultaneously the helical pitch angle was measured. Then we compared the helical pitch angels at strains below the physiological level 3 % and above.
It seems that there is a significant difference between the groups. The identification of these microstructural changes together with biomechanical data is of high importance for the field of tissue engineering.
Furthermore, the in vivo potential of SHG microscopy can play a key role in the clinical segment.