Structural or functional heterogeneity of normal human serum albumin, allo albumin, bisalbumin.

The present paper reports a comparative isoelectric focusing study of electrophoretically normal and abnormal albumins. All the albumins were purified by two different techniques (cellulose acetate electrophoresis and preparative slab isoelectric focusing), and submitted to analytical isoelectric focusing before and after incubation with either metabolites or drugs. Isoelectric focusing patterns show general heterogeneity, both in normal and in any of the observed alloalbumins. The heterogeneity is increased in bisalbumins (drug or metabolite induced), showing the same electrophoretic pattern as alloalbumins. The differences are related to the amount of the ligands. The results agree with the hypothesis that the heterogeneity depends on the structure and the carrier function of albumin.