Plasma-induced Instability of Reverse-phase Evaporation Vesicles

Abstract

Reverse-phase evaporation vesicles (REV), which have been proposed for use as drug carriers, were evaluated for stability in human plasma. A kinetic study of carboxyfluorescein (CF) leakage from REV showed that plasma caused an initial burst of CF leakage, followed by apparent recovery of the barrier function of REV membrane. The rate of phospholipid exchange between REV and high-density lipoprotein, and the changes in the turbidity of REV and in the polarization of a fluorescent probe embedded in the membrane during the incubation of REV in plasma were determined. On the basis of the results, it is suggested that the interaction of REV and plasma initially increased the permeability of REV membrane, resulting in the formation of REV with a smaller volume of water phase, and these REV were no longer susceptible to the destabilizing effect of plasma.