A simple method for the isolation of alpha-chains of different collagen types was developed. The procedure involves sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by electroelution of separated and defixed collagen alpha-chains. Collagen types I, II, III and V from different porcine tissues were recovered in high quantity (> 95%) and purity (> 98%) as evidenced by amino acid analysis. The procedure can be used for sample quantities smaller than required for conventional methods e.g. chromatographic procedures.