Isolation of skeletal muscle collagen

A new method for the isolation of a high yield of collagen from human skeletal muscle is described. This technique employs rapid stirring of the homogenate of skeletal muscle with a magnetic stirrer. Fibrous material entangled during rapid stirring was recovered by passing the homogenate through a sieve and then sequentially extracted with Hasselbach-Schneider solution and 0.6 m KI-0.06 m Na₂S₂O₃. The insoluble residue obtained after these extractions was shown to be highly purified collagen by amino acid analysis, and the recovery of collagen by this method was found to be more than 90% of the total collagen in skeletal muscle. The isolated collagen from 5 years of age was mostly composed of Type I collagen, and small amounts of Type III collagen and an unidentified collagenous protein migrating in a position near Type V collagen (αB chain) were also found on a sodium dodecyl sulfate-polyacrylamide gel.