Amphipathic and membrane-destabilizing properties of the cationic acrylate polymer Eudragit E100

The cationic acrylate polymer Eudragit E100 (E100) produces a biphasic effect on the stability of casein micelles disrupting their internal structure. These results suggested that this polymer could have some amphipathic character. Therefore, in this study the polymer was characterized with respect to its interaction with different amphipathic systems (bile-acid micelles, lipoproteins and liposomes), cell membranes (red blood cells) and virus membranes (Herpes simplex type 2 virus). As with caseins, a biphasic effect was observed with bile acids with a precipitation phase at low polymer/bile acid ratio and a solubilization phase when the polymer concentration was increased. Upon interaction with human plasma, an important reduction in cholesterol and triglycerides was observed upon remotion of E100 by a rise in pH to 8.5 and centrifugation. In agreement with this finding, an important reduction in plasma lipoproteins was observed upon its treatment with E100 and further remotion by pH rise and centrifugation. However, the amount of the major protein components of human plasma and the activity of several enzymes and antibodies were not affected by their treatment with E100. The membrane-destabilizing properties of E100 were confirmed by its lytic activity on liposomes and red blood cells and by an important antiviral effect of E100 on Herpes simplex virus type 2. Altogether, these results show that, despite its water solubility and cationic character, E100 displays a significative amphipathic and membrane-destabilizing character with potential biotechnological applications. [diagram in text].