Dye-Binding Capacity of Serum Albumin in Hemolytic Disease of the Newborn

In recent years considerable evidence has been reported in support of the theory that bilirubin is toxic to the newborn brain (bilirubin encephalopathy). It has been further suggested that perhaps free bilirubin, that which is not bound to albumin, is the toxic substance.¹ Utilizing this information, studies were done in newborn puppies which suggested a protective action for albumin against bilirubin toxicity.² It therefore seemed advisable to determine the binding capacity of albumin in the newborn, particularly in the infant with hemolytic disease.

A reduction in the capacity of serum albumin to bind anionic dyes has been reported in patients with cancer,³ severe kidney and liver disease, infections,⁴ and in pregnancy.⁵ Blondheim⁶ found that the amount of phenolsulfonphthalein bound by serum was related to the albumin concentration in excess of a critical concentration of 1.5 gm.%. He concluded that dye-binding in diseased states was