Aggregation of bilirubin in injectates and incubation media: its significance in experimental studies of CNS toxicity.

In experimental work with bilirubin toxicity, incubates or injectates are prepared without added albumin, or with a molar excess of bilirubin over albumin. Bilirubin is liable to aggregation as free bilirubin acid under these circumstances, giving rise to variable toxicity. Stable solutions are obtained with a molar excess of albumin over bilirubin; such solutions show no toxicity, however. It is suggested that this difficulty may be circumvented by using an excess of albumin, adding a sulfonamide as a bilirubin displacer, to provoke toxicity.