Effect of Functionalized Gold Nanoparticles on Floating Lipid Bilayers

Abstract

The development of novel nano-engineered materials poses important questions regarding the impact of these new materials on living systems. Possible adverse effects must be assessed in order to prevent risks for health and the environment. On the other hand, a thorough understanding of their interaction with biological systems might also result in the creation of novel biomedical applications. We present a study on the interaction of model lipid membranes with gold nanoparticles (AuNP) of different surface modifications. Neutron reflectometry experiments on zwitterionic lipid double bilayers were performed in the presence of AuNP functionalized with cationic and anionic head groups. Structural information was obtained that provided insight into the fate of the AuNPs with regard to the integrity of the model cell membranes. The AuNPs functionalized with cationic head groups penetrate into the hydrophobic moiety of the lipid bilayers and cause membrane disruption at an increased concentration. In contrast, the AuNPs functionalized with anionic head groups do not enter but seem to impede the destruction of the lipid bilayer at an alkaline pH. The information obtained might influence the strategy for a better nanoparticle risk assessment based on a surface charge evaluation and contribute to nano-safety considerations during their design.

The effect of the protein corona on the interaction between nanoparticles and lipid bilayers

“…Data were analyzed using Motofit, as previously described 33 allowing simultaneous fitting of data sets from the same sample under different contrast conditions. Two operating approaches were applied: 1) each block in the system is considered independent of the adjacent ("Rfit"); 2) the model is reparametrized using physically relevant parameters to reduce the covariance of some parameters ("Gfit").…”

“…In fact, while QCM-D gives information about the "wet mass" adsorbed (hydration water included) in terms of amount and viscoelastic properties of the surface layer, NR provides a structural characterization of the membrane in terms of thickness, roughness, hydration and selective composition of the tail and head regions of the membrane at a resolution able to quantify how these attributes are altered by the interaction with the nanomaterial. 33 The combination of the two techniques allowed highlighting even the smallest change in the SLB structure following the interaction with the NPs.…”

Driving Adsorbed Gold Nanoparticle Assembly by Merging Lipid Gel/Fluid Interfaces

“…For example, zwitterionic phosphocholine (PC) liposomes can adsorb a diverse range of nanomaterials, including latex beads, 8,9 TiO2, [10][11][12] graphene oxide, 13,14 nano-diamonds, 15 and gold NPs (AuNPs). [16][17][18][19][20][21][22] Among these materials, AuNPs are particularly interesting: 1) the surface chemistry of AuNPs can be readily controlled by capping with thiol ligands; 2) AuNPs display distance-dependent color due to surface plasmon coupling, allowing convenient visual monitoring; 23 and 3) AuNPs have strong van der Waals interaction (i.e. large Hamaker constant) with other surfaces thus making strong physisorption possible.…”

Preparation and characterization of cationic Pluronic for surface modification and functionalization of polymeric drug delivery nanoparticles

“…the surface immobilization of targeting ligands on the NP surface. In addition to that the presence of positively charged molecules on a nanoparticle surface enhances their nonspecific membrane affinity [23,30]. It is however, an open question how these cationic derivatives change the physico-chemical properties of PLGA NPs compared to the systems stabilized with Pluronics.…”