Structural Characterisation of Nanoparticle-Supported Lipid Bilayers by Grazing Incidence X-ray and Neutron Scattering

Paracini, N.; Gutfreund, P.; Welbourn, R.; Gonzales, J. F.; Zhu, K.; Miao, Y.; Nageshwar, Y.; Darwish, T. A.; Garvey, C.; Waldie, S.; Larsson, J.; Wolff, M.; Cardenas, M.

doi:10.1101/2022.07.07.499146

bioRxiv · 10.1101/2022.07.07.499146

Structural Characterisation of Nanoparticle-Supported Lipid Bilayers by Grazing Incidence X-ray and Neutron Scattering

Paracini, N.·Gutfreund, P.·Welbourn, R.·Gonzales, J. F.·Zhu, K.·Miao, Y.·Nageshwar, Y.·Darwish, T. A.·Garvey, C.·Waldie, S.·Larsson, J.·Wolff, M.·Cardenas, M.

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Abstract

The structure of supported lipid bilayers formed on a monolayer of nanoparticles was determined using a combination of grazing incidence X-ray and neutron scattering techniques. Ordered nanoparticle arrays assembled on a silicon crystal using a Langmuir-Schaefer deposition were shown to be suitable and stable substrates for the formation of curved and fluid lipid bilayers that retained lateral mobility, as shown by fluorescence recovery after photobleaching. A comparison between the structure of the curved bilayer assembled around the nanoparticles with the planar lipid membrane formed on the flat underlying silicon oxide surface revealed a [~]5 [A] thinner bilayer on the curved interface, resolving the effects of curvature on the lipid packing and overall bilayer structure. The combination of neutron scattering techniques, which grant access to sub-nanometre scale structural information at buried interfaces, and nanoparticle-supported lipid bilayers, offers a novel approach to investigate the effects of membrane curvature on lipid bilayers.

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Paracini, N., Gutfreund, P., Welbourn, R., Gonzales, J. F., Zhu, K., Miao, Y., Nageshwar, Y., Darwish, T. A., Garvey, C., Waldie, S., Larsson, J., Wolff, M., Cardenas, M.. 2022-07-08. Structural Characterisation of Nanoparticle-Supported Lipid Bilayers by Grazing Incidence X-ray and Neutron Scattering. https://doi.org/10.1101/2022.07.07.499146

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