Tuning stable noble metal nanoparticles dispersions to moderate their interaction with model membranes

Hypothesis: The properties of stable gold (Au) nanoparticle dispersions can be tuned to alter their activity towards biomembrane models. Experiments: Au nanoparticle coating techniques together with rapid electrochemical screens of a phospholipid layer on fabricated mercury (Hg) on platinum (Pt) electrode have been used to moderate the phospholipid layer activity of Au nanoparticle dispersions. Screening results for Au nanoparticle dispersions were intercalibrated with phospholipid large unilamellar vesicle (LUV) interactions using a carboxyfluorescein (CF) leakage assay. All nanoparticle dispersions were characterised for size, by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Findings: Commercial and high quality home synthesised Au nanoparticle dispersions are phospholipid monolayer active whereas Ag nanoparticle dispersions are not. If Au nanoparticles are coated with a thin layer of Ag then the particle/lipid interaction is suppressed. The electrochemical assays of the lipid layer activity of Au nanoparticle dispersions align with LUV leakage assays of the same. Au nanoparticles of decreasing size and increasing dispersion concentration showed a stronger phospholipid monolayer/bi-layer interaction. Treating Au nanoparticles with cell culture medium and incubation of Au nanoparticle dispersions in phosphate buffered saline (PBS) solutions removes their phospholipid layer interaction. (c) 2021 Elsevier Inc. All rights reserved.

Automated summary

The properties of stable gold nanoparticle dispersions can be modified to affect their activity towards biomembrane models. Gold nanoparticle dispersions exhibit phospholipid monolayer activity, while silver nanoparticle dispersions do not. Coating gold nanoparticles with a thin layer of silver suppresses the particle/lipid interaction.