RT Journal Article
SR Electronic
T1 Ion-bridges and lipids drive aggregation of same-charge nanoparticles on lipid membranes
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2021.11.22.468803
DO 10.1101/2021.11.22.468803
A1 Lavagna, Enrico
A1 Bochicchio, Davide
A1 De Marco, Anna L.
A1 Güven, Zekiye P.
A1 Stellacci, Francesco
A1 Rossi, Giulia
YR 2021
UL http://biorxiv.org/content/early/2021/11/22/2021.11.22.468803.abstract
AB The control of the aggregation of biomedical nanoparticles (NP) in physiological conditions is crucial as clustering may change completely the way they interact with the biological environment. Here we show that Au nanoparticles, functionalized by an anionic, amphiphilic shell, spontaneously aggregate in fluid zwitterionic lipid bilayers. We use Molecular Dynamics and enhanced sampling techniques to disentangle the short-range and long-range driving forces of aggregation. At short inter-particle distances, ion-mediated, charge-charge interactions (ion bridging) stabilize the formation of large NP aggregates, as confirmed by cryo-electron microscopy. Lipid depletion and membrane curvature are the main membrane deformations driving long-range NP-NP attraction. Ion bridging, lipid depletion, and membrane curvature stem from the configurational flexibility of the nanoparticle shell. Our simulations show, more in general, that the aggregation of same-charge membrane inclusions can be expected as a result of intrinsically nanoscale effects taking place at the NP-NP and NP-bilayer soft interfaces.Competing Interest StatementThe authors have declared no competing interest.