Effects of dehydrothermal treatment on collagen

Abstract

Collagen is the most fundamental unit of the extra cellular matrix and is found in most mammal tissues such as the tendon, cartilage, bone and skin. Due to its excellent biocompatibility, collagen is often used as a matrix for cell infiltration in many tissue regenerative applications. The success of these scaffolds in an in vivo environment is determined mainly by the mechanical and structural properties of the scaffold. Therefore, a study was carried out to investigate the effects of different dehydrothermal (DHT) treatment timings on the mechanical properties of type 1 collagen obtained from the sheep stifle joint.

The samples were air dried for 24 hours before DHT treatment was carried out for 30 minutes, 2, 4 and 24 hours at 120°C. After DHT treatment, the fibers were subjected to tensile testing and information about the mechanical behavior of the collagen fibers was assessed through the analysis of the modulus of elasticity, ultimate tensile strength, strain at maximum stress and strain energy density up to maximum stress. The graphs, statistical tests and Weibull probability distribution showed an overall enhancement in the stiffness, strength and toughness of the fibers as the exposure time increased; while the strain at maximum stress showed increment only after 24 hours of treatment. The enhancements in mechanical properties were attributed to the increase in crosslink density between the amino acid chains and the shortening of the increase in molecular packing density due to the tilting of fibrils in the gap region.