Effect of Liposome Surface Charge and Rigidity on Interaction with Gold Nanoparticles

Liposomes and cell membranes have in common the outer double lipid membrane, and their compositions usually includes phosphatidylcholine lipids. Therefore, liposomes can be used as a proxy to study cell membrane stability and interactions with nanomaterials. To investigate liposome/AuNP interaction, liposomes of different phosphocholine composition and phase with zwitterionic, negative and positive surface charges in liquid and gel state are fabricated and blended with monodisperse gold nanoparticles (AuNP). The resulting systems are then characterized by a combination of techniques, namely, DLS, ELS, UV-Vis, SAXS, and TEM. Our Results show significant differences in liposome/nanoparticle interactions between the samples under study. This leads to different strength of interaction and levels of AuNP aggregation, depending on the membrane rigidity as well as sign and strength of the liposome surface charge.