The dendrimer impact on vesicles can be tuned based on the lipid bilayer charge and the presence of albumin

Abstract

PAMAM (polyamidoamine) dendrimers are promising polymers in biomedical applications that can interact with both the lipid bilayer and proteins. Here we employed giant unilamellar vesicles (GUVs) of two different charge densities to study the effect of albumin, one of the major proteins in blood plasma, on the interactions between PAMAM dendrimers and lipid membranes. The results show that albumin exacerbates the effect of dendrimers on the destabilization of the vesicles in terms of leakage, aggregation and collapse in particular for negatively charged vesicles while neutrally charged membranes are not affected. We conclude that the higher affinity of both albumin and PAMAM G6 towards negatively charged membranes explains their synergistic behavior in this case. In the case of neutral vesicles, the affinity between PAMAM G6 and albumin is stronger than that between PAMAM G6 (or albumin) and neutral vesicles, and thus no synergism is observed for the mixture during the interaction with neutral membranes.