Kinetics of surfactant-induced release from liposomes: a time-dependent permeability model

The article examines membrane permeabilization and the consequent content r elease of lipid vesicles due to the addition of surfactant. Experimental re sults show that content release involves a complex kinetics where almost in stantaneous release is followed by prolonged slow leakage. The model propos ed therefore regards bilayer permeability as varying with the time elapsed from the moment of surfactant addition. A delta function followed by an exp onentially decaying profile is assumed for these permeability curves. The e ffects of surfactant concentration and type (Triton X-100, Tween 20 and Twe en 60) can be compared by comparing the fitting parameters of the permeabil ity curves. (C) 2000 Elsevier Science B.V. All rights reserved.