THE SONIC FRAGMENTATION OF COLLAGEN MACROMOLECULES

Abstract

The exposure of soluble calk-skin collagen to 9-kilocycle sonic irradiation at low temperature causes fragmentation of the long, rodlike collagen macromolecules into shorter pieces that retain the three-stranded, helical structure. A series of samples produced by varying the time of exposure from 10 to 440 minutes were found to have molecular weights in the range of 335,000-140,000. The intrinsic viscosity of these samples depended on the 1.80 power of the molecular weight, and the sedimentation constant on the 0.20 power. This dependence was compatible with behavior expected of homologous, rod-like molecules of 13.6 A[degree] diameter (solvated). The time-dependence of the molecular weight change is compatible with preferential fracture of the collagen macromolecule into halves and quarters.