Global SAXS data analysis for multilamellar vesicles: Evolution of the scattering density profile (SDP) model

Peter Heftberger; Benjamin Kollmitzer; Frederick A. Heberle; Jianjun Pan; Michael Rappolt; Heinz Amenitsch; Norbert Kucerka; John Katsaras; Georg Pabst

arXiv · 1309.5237

Global SAXS data analysis for multilamellar vesicles: Evolution of the scattering density profile (SDP) model

Peter Heftberger·Benjamin Kollmitzer·Frederick A. Heberle·Jianjun Pan·Michael Rappolt·Heinz Amenitsch·Norbert Kucerka·John Katsaras·Georg Pabst

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Abstract

We adapted the highly successful scattering density profile (SDP) model, which is used to jointly analyze small angle x-ray and neutron scattering data from unilamellar vesicles, for use with data from fully hydrated, liquid crystalline multilamellar vesicles (MLVs). By using a genetic algorithm, this new method is capable of providing high resolution structural information, as well as determining bilayer elastic bending fluctuations from standalone x-ray data. Important structural parameters, such as bilayer thickness and area per lipid were determined for a series of saturated and unsaturated lipids, as well as binary mixtures with cholesterol. Results are in good agreement with previously reported SDP data, which used both neutron and x-ray data. The addition of deuterated and non-deuterated MLV neutron data to the analysis improved lipid backbone information, but did not improve, within experimental uncertainties, the structural information regarding bilayer thickness and area per lipid.

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Peter Heftberger, Benjamin Kollmitzer, Frederick A. Heberle, Jianjun Pan, Michael Rappolt, Heinz Amenitsch, Norbert Kucerka, John Katsaras, Georg Pabst. 2013-09-20. Global SAXS data analysis for multilamellar vesicles: Evolution of the scattering density profile (SDP) model. https://arxiv.org/abs/1309.5237

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