Quantitative assessment of human erythrocyte membrane solubilization by Triton X-100

We report here a quantitative analysis of the interaction of the non-ionic surfactant Triton X-100 with human erythrocyte membranes. By applying a classical treatment for the interpretation of the action of surface active compounds to the hemolytic curves, we could calculate parameters such as Re—the effective surfactant/lipid molar ratio for erythrocyte membrane saturation (Resat) and total lysis (Resol)—and Kb, the binding constant of Triton X-100 to human erythrocyte membranes. The Kb (5900 M−1) and Re (1.58 and 2.14) values presented here are in good agreement with literature data for Triton X-100 solubilization of model phospholipid membranes.