Abstract

Multicomponent lipid bilayers are used as models for searching the origin of spatial heterogeneities in biomembranes called lipid rafts, implying the coexistence of domains of different phases and compositions within the lipid bilayer. The spatial organization of multicomponent lipid bilayers on a scale of a hundred nanometers remains unknown. Brillouin spectroscopy providing information about the acoustic phonons with the wavelength of several hundred nanometers has an unexplored potential for this problem. Here, we applied Brillouin spectroscopy for three binary bilayers composed of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), 1,2-palmitoyl-sn-glycero-3-phosphocholine (DPPC), and cholesterol. The Brillouin experiment for the oriented planar multibilayers was realized for two scattering geometries involving phonons for the lateral and normal directions of the propagation. The DPPC–DOPC mixtures known for the coexistence of the solid-ordered and liquid-disordered phases had bimodal Brillouin peaks, revealing the phase domains with sizes more than a hundred nanometers. Analysis of the Brillouin data for the binary mixtures concluded that the lateral phonons are preferable for testing the lateral homogeneity of the bilayers, while the phonons spreading across the bilayers are sensitive to the layered packing at the mesoscopic scale.

© 2022 The Author(s)

Visualization and measurement of the local absorption coefficients of single bilayer phospholipid membranes using scanning near-field optical microscopy

Arif M. Siddiquee, Imad Younus Hasan, Shibiao Wei, Daniel Langley, Eugeniu Balaur, Chen Liu, Jiao Lin, Brian Abbey, Adam Mechler, and Shanshan Kou
Biomed. Opt. Express 10(12) 6569-6579 (2019)

Use of attenuated total reflectance Fourier transform infrared spectroscopy to monitor the development of lipid aggregate structures

Mateo R. Hernandez, Elyse N. Towns, Terry C. Ng, Brian C. Walsh, Richard Osibanjo, Atul N. Parikh, and Donald P. Land
Appl. Opt. 51(15) 2842-2846 (2012)

Sub-wavelength infrared imaging of lipids

Fiona Yarrow, Eamonn Kennedy, Frederic Salaun, and James H. Rice
Biomed. Opt. Express 2(1) 37-43 (2011)

Measurement of membrane rigidity on trapped unilamellar phospholipid vesicles by using differential confocal microscopy

Tze-Hsuan Liu, Jian-Long Xiao, Chau-Hwang Lee, and Jiunn-Yuan Lin
Appl. Opt. 50(19) 3311-3315 (2011)

Surface plasmon resonance as detection tool for lipids lateral mobility in biomimetic membranes

Giancarlo Margheri, Riccardo D’Agostino, Lucia Becucci, Rolando Guidelli, Bruno Tiribilli, and Mario Del Rosso
Biomed. Opt. Express 3(12) 3119-3126 (2012)