Disruption of liposomes by tetracaine micelles

The effect of the local anesthetic tetracaine hydrochloride on the stability of egg lecithin vesicles has been studied by means of a filtration procedure using Pellicon membranes with an average molecular weight limit of retention of 10(5). These filters were efficient to retain liposomes and allowed the free passage of disrupted vesicles as detected by measuring the phospholipid content in the filtrates. It has been found that at concentrations above 0.05 M, the anesthetic induces disruption of liposomes presumably through formation of mixed micelles of tetracaine and phosphatidylcholine.