Nanoplasmonic Ruler for Measuring Separation Distance between Supported Lipid Bilayers and Oxide Surfaces

0499898 - ÚFE 2019 RIV US eng J - Journal Article
Ferhan, A.R. - Špačková, Barbora - Jackman, J.A. - Ma, G.J. - Sut, T.N. - Homola, Jiří - Cho, N.J.
Nanoplasmonic Ruler for Measuring Separation Distance between Supported Lipid Bilayers and Oxide Surfaces.
Analytical Chemistry. Roč. 90, č. 21 (2018), s. 12503-12511. ISSN 0003-2700. E-ISSN 1520-6882
R&D Projects: GA ČR(CZ) GBP205/12/G118
Institutional support: RVO:67985882
Keywords : Gold coatings * Supported lipid bilayers * Surface plasmon resonance
OECD category: Optics (including laser optics and quantum optics)
Impact factor: 6.350, year: 2018

Unraveling the details of how supported lipid bilayers (SLBs) are coupled to oxide surfaces is experimentally challenging, and there is an outstanding need to develop highly surface-sensitive measurement strategies to determine SLB separation distances. Indeed, subtle variations in separation distance can be associated with significant differences in bilayer-substrate interaction energy. Herein, we report a nanoplasmonic ruler strategy to measure the absolute separation distance between SLBs and oxide surfaces. A localized surface plasmon resonance (LSPR) sensor was employed to track SLB formation onto titania- and silica-coated gold nanodisk arrays. To interpret measurement data, an analytical model relating the LSPR measurement response to bilayer-substrate separation distance was developed based on finite-difference time-domain (FDTD) simulations and theoretical calculations. The results indicate that there is a larger separation distance between SLBs and titania surfaces than silica surfaces, and the trend was consistent across three tested lipid compositions. We discuss these findings within the context of the interfacial forces underpinning bilayer-substrate interactions, and the nanoplasmonic ruler strategy provides the first direct experimental evidence comparing SLB separation distances on titania and silica surfaces
Permanent Link: http://hdl.handle.net/11104/0292086