Multiple stages of detergent-erythrocyte membrane interaction-A spin label study

► A complex series of events takes place when increasing concentrations of TTX-100 interact with whole red blood cells. ► Detergent binding promoted an increase in permeability, leading to cell lysis. ► The molecular packing accessed by Electron Paramagnetic Resonance, in whole cell suspensions, pellets, and supernatants was very similar until higher detergent concentrations were added. ►Supernatants initially consisted of membrane fragments probably kept in suspension by the formation of edges by detergent molecules surrounding the borders of these fragments, but further detergent addition promoted membrane-to-micelle transition and the aggregates (containing high proportions of detergent) approached the molecular packing of pure TTX-100 micelles.