Isolation of fibronectin under mild conditions.

Fibronectin was isolated from human blood plasma by affinity chromatography on immobilized Physiogel, a plasma expander made by chemical degradation of gelatin. Binding of fibronectin to Physiogel is weaker than to gelatin; elution could therefore be performed under rather mild conditions: at pH 6.5 and 30 degrees C. Loading of the sample at low temperature increases the capacity of the affinity column.