Abstract
To determine whether a purified serum albumin is metabolically native, it is compared in simultaneous turnover studies with unfractionated plasma. Albumin is iodinated with 125I or 131I, the plasma with the opposite isotope. In the albumin band of gel electrophoresis on daily plasma samples the ratio between the count rate of 131I and 125I must keep constant throughout the study if the purified albumin is native. If it is denatured, the true plasma disappearance rate can be calculated from the plasma activities of the denatured albumin and the ratios.