Abstract
Fibronectin was purified from human plasma by affinity chromatography under nondenaturing conditions. The method was based on the previously known binding of fibronectin to gelatin. The novel features of our method are the use of arginine in the elution of fibronectin from immobilized gelatin [Vuento & Vaheri (1978) Biochem. J. 175, 333-336] and the use of arginine-agarose as second affinity step. The purified protein was homogeneous as judged by polyacrylamide-gel electrophoresis, analytical ultracentrifugation and two-dimensional immunoelectrophoresis. The yield was 60%. We propose that the method would be useful in preparation of fibronectin for studies on its biological activities, where it is important that the protein is obtained in a native state.