A simple and reliable method for the purification of human alphafetoprotein (AFP) from amniotic fluid and fetal...

Highly purified human alphafetoprotein has been isolated from amniotic fluid and fetal livers by a combination of salting-out, and gel filtration, ion exchange, and concanavalin-A affinity chromatography. They yield ranged from 25 to 37%, and purity was demonstrated by radioimmunodiffusion, crossed radioimmunoelectrophoresis, polyacrylamide gel electrophoresis, and comparison with other preparations by radioimmunoassay. Immunochemical potency by weight of alphafetoprotein purified from amniotic fluid was similar to that from fetal liver, with molecular weights of 70 000 and 68 500 respectively. The amino acid and carbohydrate composition is also reported. This physicochemical method is relatively simple and inexpensive and is well suited for large scale production.