Design of lipid-based nanocarriers via cation modulation of ethanol-interdigitated lipid membranes

DOI: 10.1021/acs.langmuir.1c02076

Authors: Valeria Nele (Imperial College London) , Margaret N. Holme (Imperial College London; Karolinska Institutet) , M. Harunur Rashid (RMIT University; North South University) , Hanna M. G. Barriga (Karolinska Institutet) , Tu C. Le (RMIT University) , Michael R. Thomas (Imperial College London; University College London (UCL)) , James J. Doutch (ISIS Neutron and Muon Source) , Irene Yarovsky (RMIT University) , Molly M. Stevens (Imperial College London; Karolinska Institutet)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Langmuir , VOL 5

State: Published (Approved)
Published: September 2021
Diamond Proposal Number(s): 18658

Abstract: Short-chain alcohols (i.e., ethanol) can induce membrane interdigitation in saturated-chain phosphatidylcholines (PCs). In this process, alcohol molecules intercalate between phosphate heads, increasing lateral separation and favoring hydrophobic interactions between opposing acyl chains, which interpenetrate forming an interdigitated phase. Unraveling mechanisms underlying the interactions between ethanol and model lipid membranes has implications for cell biology, biochemistry, and for the formulation of lipid-based nanocarriers. However, investigations of ethanol–lipid membrane systems have been carried out in deionized water, which limits their applicability. Here, using a combination of small- and wide-angle X-ray scattering, small-angle neutron scattering, and all-atom molecular dynamics simulations, we analyzed the effect of varying CaCl2 and NaCl concentrations on ethanol-induced interdigitation. We observed that while ethanol addition leads to the interdigitation of bulk phase 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) bilayers in the presence of CaCl2 and NaCl regardless of the salt concentration, the ethanol-induced interdigitation of vesicular DPPC depends on the choice of cation and its concentration. These findings unravel a key role for cations in the ethanol-induced interdigitation of lipid membranes in either bulk phase or vesicular form.

Journal Keywords: Vesicles; Lipids; Ethanol; Ions; Membranes

Subject Areas: Chemistry


Instruments: I22-Small angle scattering & Diffraction

Other Facilities: SANS2D at ISIS

Added On: 30/09/2021 21:55

Discipline Tags:

Soft condensed matter physics Chemistry Organic Chemistry

Technical Tags:

Scattering Small Angle X-ray Scattering (SAXS) Wide Angle X-ray Scattering (WAXS)