The effect of extraction, animal age and post mortem storage on tendon collagen. A differential scanning calorimetric study

Summary Differential scanning calorimetry was used to study the collagen denatured collagen transition in tendon collagen. It was found that purification of collagen by salt (KCI) and trypsin caused a slight, but significant, decrease in the transition temperature, but no significant change in the enthalpy, ΔHD, of the transition. Animal age (0-6 years) had no significant effect on either ΔHD (mean value = 1293 ± 72 cal. amino acid residue−1) or the extrapolated onset temperature, T0, (334.2 ± 0.3°K) of the transition in untreated tendon. However, the amount of collagen melting after 340°K increased markedly with age (from 0 to about 250 mg/g of tendon) although the amount melting before 340°K was approximately constant, 138 ± 17 mg/g tendon. Upon storage at 1 ± 1°C for 2 weeks 7 out of 16 tendons became less stable as judged by decreases in T0 and increases in the amount of collagen melting before 340°K. Two of the tendons became more stable as judged by increases in T0 and decreases in the amount melting before 340°K. These results are briefly discussed.