Speaker
Dr
Inkeri Kontro
(University of Helsinki)
Description
Ionic liquids (ILs) are solvents that have many desirable properties. For example, they are easier to handle than volatile organic solvents and they dissolve cellulose. However, many are harmful. The toxicity of ILs is in part due to their effects on cell membranes. In this study, we have observed effects of (tetradecyl)tributylphosphonium acetate ([P$_{14444}$][OAc]), trioctylmethylphosphonium acetate ([P$_{8881}$][OAc]), tributylmethylphosphonium acetate ([P$_{4441}$][OAc]) and 1-ethyl-3-methylimidazolium acetate ([emim][OAc]) on model membranes composed of L-α-phosphatidylcholine multilamellar vesicles (MLV) by time-resolved small-angle X-ray scattering (SAXS).
The SAXS experiments were conducted on beamline ID02 at ESRF, Grenoble. The penetration of ILs into MLVs was studied at millisecond resolution using a stopped-flow mixing device. The results show that all studied ILs penetrated the lipid bilayers. [emim][OAc] and [P$_{4441}$][OAc] caused a thinning of the lamellar distance but did not induce disorder in the lamellae. The ILs with larger cations destroy the lamellar order. The results give insight into the ways in which ILs can penetrate the cell membrane and cause changes to it.
Primary author
Dr
Inkeri Kontro
(University of Helsinki)
Co-authors
Dr
Antti Rantamäki
(University of Helsinki)
Dr
Kirsi Svedström
(University of Helsinki)
Dr
Patrik Ahvenainen
(University of Helsinki)
Dr
Susanne Wiedmer
(University of Helsinki)
