The influence of bilirubin on fluidity and rotational correlation times of human erythrocyte membrane.

The effects of bilirubin on the membrane motion parameters of human erythrocyte membrane were determined by the spin labelled ESR method. It causes a decrease in the order parameter and an increase in the corresponding fluidity of the lipid molecules. Bovine serum albumin was found to inhibit effectively the effects due to bilirubin. The disturbance to the organization of membrane molecules by bilirubin as well as the protective effects of serum albumin are discussed on the basis of the experimental results.