Preliminary investigations of intrinsic and extrinsic optical activity as purity criterion for human serum albumins.

Induced circular dichroism measurements were made to follow the binding of four acidic drugs to two lots of crystalline and two lots of fraction V human serum albumins. The magnitude of the induced circular dichroism varied with all lots of albumin, suggesting a strong sensitivity of the phenomenon to small changes in purity or secondary structure of the albumins. The circular dichroism of the albumins themselves showed much less variation. The more classical analytical techniques of UV absorption, measurement of absorption following methyl orange binding, gel electrophoresis, and ultracentrifugation were also performed on the albumins for comparison.