TY - JOUR
T1 - Organization of lipid mixtures containing a pyrene amphiphile in liposomes and Langmuir monolayers
T2 - Evidence of superlattice arrangement
AU - Gradella Villalva, Denise
AU - Diociaiuti, Marco
AU - Giansanti, Luisa
AU - Petaccia, Manuela
AU - Mancini, Giovanna
PY - 2018/9/20
Y1 - 2018/9/20
N2 - Phase properties and lateral distribution of components in lipid membranes are frequently investigated by fluorescence of pyrene-labeled lipids. In particular conditions, at specific component molar fractions, lipid bilayers can present regions organized in regular arrangements, hexagonal lattices, where the acyl chain form regular patterns around the pyrene tagged chain of the labeled component. Liposomes composed of a pyrenyl twin type amphiphile (1) bearing a pyrrolidinium headgroup and either 1,2-dimyristoyl-sn-glycero-phosphocholine or 1,2-dioleoyl-sn-glycero-phosphocholine were investigated by fluorescence spectroscopy and Langmuir compression isotherm techniques in a restricted range of molar fraction, X1, (0.005-0.15) to evaluate the influence of composition, temperature and curvature radius on lipid organization and to assess the eventual organization in super lattice arrangements. Amphiphile 1 presents different characteristics with respect to the Pyr-PC usually used in similar investigations, both in terms of charge and conformational freedom, and its presence has a significant effect on membrane organization. Our results put in evidence that both temperature and the presence of unsaturation strongly influence the presence of hexagonal lattice in lipid bilayers.
AB - Phase properties and lateral distribution of components in lipid membranes are frequently investigated by fluorescence of pyrene-labeled lipids. In particular conditions, at specific component molar fractions, lipid bilayers can present regions organized in regular arrangements, hexagonal lattices, where the acyl chain form regular patterns around the pyrene tagged chain of the labeled component. Liposomes composed of a pyrenyl twin type amphiphile (1) bearing a pyrrolidinium headgroup and either 1,2-dimyristoyl-sn-glycero-phosphocholine or 1,2-dioleoyl-sn-glycero-phosphocholine were investigated by fluorescence spectroscopy and Langmuir compression isotherm techniques in a restricted range of molar fraction, X1, (0.005-0.15) to evaluate the influence of composition, temperature and curvature radius on lipid organization and to assess the eventual organization in super lattice arrangements. Amphiphile 1 presents different characteristics with respect to the Pyr-PC usually used in similar investigations, both in terms of charge and conformational freedom, and its presence has a significant effect on membrane organization. Our results put in evidence that both temperature and the presence of unsaturation strongly influence the presence of hexagonal lattice in lipid bilayers.
KW - Curvature
KW - Langmuir compression isotherms
KW - Liposomes
KW - Radius
KW - Superlattice arrangement
KW - Temperature
KW - Unsaturation
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U2 - 10.1016/j.colsurfa.2018.05.057
DO - 10.1016/j.colsurfa.2018.05.057
M3 - Article
AN - SCOPUS:85048482952
SN - 0927-7757
VL - 553
SP - 417
EP - 424
JO - Colloids and Surfaces A: Physicochemical and Engineering Aspects
JF - Colloids and Surfaces A: Physicochemical and Engineering Aspects
ER -