Abstract
While mixing nanoparticles with certain
biological molecules can result in coronas that afford some control over how engineered
nanomaterials interact with living systems, corona formation mechanisms remain
enigmatic. Here, we report spontaneous lipid
corona formation, i.e. without active mixing, upon attachment to stationary lipid
bilayer model membranes and bacterial cell envelopes, and present ribosome-specific
outcomes for multi-cellular organisms. Experiments show that polycation-wrapped
particles disrupt the tails of zwitterionic lipids, increase bilayer fluidity, and
leave the membrane with reduced ζ-potentials. Computer simulations show contact
ion pairing between the lipid headgroups and the polycations’ ammonium groups leads
to the formation of stable, albeit fragmented, lipid bilayer coronas, while microscopy
shows fragmented bilayers around nanoparticles after interacting with Shewanella oneidensis. Our mechanistic insight
can be used to improve control over nano-bio interactions and to help understand
why some nanomaterial/ligand combinations are detrimental to organisms, like Daphnia magna, while others are not.