Abstract
Samples of turkey tendon at different degree of calcification have been investigated by high and small angle X-ray diffraction techniques using conventional and synchrotron radiation sources. The results indicate that the small angle diffraction patterns of samples at a degree of calcification ranging from 20 to 60% wt are due to the apatite phase which fits in the main band of collagen fibrils and exhibits the same axial D-periodicity, 67.0 nm, as native collagen fibrils in either wet or air-dried conditions. Analysis of these patterns reveals that the mineral phase is deposited along the collagen fibrils according to a step function. The length of the step is 0.46 D independent of the degree of calcification, while the height of the step increases with increasing calcification. The shift of the high angle equatorial diffraction spacing from 1.42 to 1.24 nm when the inorganic phase content passes from 40 to 60% wt suggests that needle-shaped crystals which compress the molecules are preferentially deposited during the advanced stages of calcification, in agreement with previuos electron microscopy observations. The structural relationship between inorganic deposits and collagen matrix is similar to that found for single osteons. This similarity increases as calcification proceeds.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call