Purification of human urinary erythropoietin on controlled-pore glass and silicic acid

Erythropoietin (Epo) has been isolated from raw human urine of anemic patients by controlled-pore glass and silicic acid chromatography. A purification factor of not less than 100-fold and recovery of about 80% of activity was routinely achieved. The resulting Epo preparation is active both in vivo and in vitro and can be neutralized by an antibody to human Epo indicating the native state and identity of the isolated Epo molecule. The preparation is stable at near neutral pH and is amenable to further purification.