Probing the Separation Distance between Biological Nanoparticles and Cell Membrane Mimics Using Neutron Reflectometry with Sub-Nanometer Accuracy

• DOI: 10.1021/jacs.2c08456
• Publication Date: 2022-11-03T12:12:25Z
• Authors: Antonius Armanious; Yuri Gerelli; Samantha Micciulla; Hudson P. Pace; Rebecca J. L. Wel...; Mattias Sjöberg; Björn Agnarsson; Fredrik Höök
• Keywords: Neutron reflectometry; Reflectometry; Nanometre; Nanobiotechnology; Biomolecule

Nanoparticle interactions with cellular membranes are controlled by molecular recognition reactions and regulate a multitude of biological processes, including virus infections, nanoparticle-mediated communication, drug delivery applications. Aided the design various supported cell membrane mimics, multiple methods have been employed to investigate these types interactions, revealing information on nanoparticle coverage, interaction kinetics, as well binding strength; however, precise quantification separation distance across which delicate occur remains elusive. Here, we demonstrate that carefully designed neutron reflectometry (NR) experiments followed an attentive selection application suitable theoretical models offer means quantify separating nanoparticles from lipid bilayer (SLB) sub-nanometer precision. The between SLBs was tuned exploiting either direct adsorption or specific using DNA tethers different conformations, distances around 1, 3, 7 nm nanometric accuracy. We also show NR provides size distribution, material composition, potential structural changes in underlying planar SLB induced upon binding. precision parameters could be quantified should pave attractive path for investigations interfaces at length scales resolutions were previously inaccessible. This thus makes it possible to, example, gain in-depth understanding inorganic membranes.