Thermal (in)stability of type I collagen fibrils

• Main Authors: Gevorkian, S. G, Allahverdyan, A. E, Gevorgyan, D. S, Simonian, A. L
• Format: Journal Article
• Language: English
• Published: 22-10-2008
• Subjects: Physics - Materials Science; Physics - Soft Condensed Matter; Quantitative Biology - Biomolecules
• DOI: 10.48550/arxiv.0810.4172

We measured Young's modulus at temperatures ranging from 20 to 100 ^{\circ}$C
for a collagen fibril taken from rat's tendon. The hydration change under
heating and the damping decrement were measured as well. At physiological
temperatures $25-45^{\circ}$C Young's modulus decreases, which can be
interpreted as instability of collagen. For temperatures between
$45-80^{\circ}$C Young's modulus first stabilizes and then increases with
decreasing the temperature. The hydrated water content and the damping
decrement have strong maxima in the interval $70-80^{\circ}$C indicating on
complex inter-molecular structural changes in the fibril. All these effects
disappear after heat-denaturating the sample at $120^\circ$C. Our main result
is a five-stage mechanism by which the instability of a single collagen at
physiological temperatures is compensated by the interaction between collagen
molecules within the fibril.