Restoring structural parameters of lipid mixtures from small-angle X-ray scattering data

Konarev P, Gruzinov A, Mertens H, Svergun D, Journal of Applied Crystallography 54(1) (2021) DOI

SASDG92 – 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) vesicles: 30 nm filter extrusion

MWexperimental 1 kDa
MWexpected 1 kDa
log I(s) 3.54×103 3.54×102 3.54×101 3.54×100
1,2-dipalmitoyl-sn-glycero-3-phosphocholine small angle scattering data  s, nm-1
1,2-dipalmitoyl-sn-glycero-3-phosphocholine Kratky plot 1.104 0 3 sRg
1,2-dipalmitoyl-sn-glycero-3-phosphocholine pair distance distribution function Rg: 23.8 nm 0 Dmax: 66 nm

Data validation

Fits and models

log I(s)
 s, nm-1
1,2-dipalmitoyl-sn-glycero-3-phosphocholine OTHER [STATIC IMAGE] model

Synchrotron SAXS data from solutions of DPCC vesicles in water, pH 7 were collected on the EMBL P12 beam line at the PETRA III storage ring (Hamburg, Germany) using a Pilatus 2M detector at a sample-detector distance of 3.1 m and at a wavelength of λ = 0.124 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). One solute concentration of 10 mg/ml was measured at 45°C. 20 successive 0.050 second frames were collected. The data were normalized to the intensity of the transmitted beam and radially averaged; the scattering of the solvent-blank was subtracted.

DPPC vesicles were extruded through 30 nm pore-diameter filter prior to analysis. Experimental molecular weight estimates do not apply in this instance (in context of the inherent size-distribution, inter-vesicle interactions and multiple contrasts of the sample) and therefore the MW of one DPPC molecule is quoted. The resulting fit to the data and corresponding plot reflects the relative electron density profile perpendicular to the DPPC bilayer of the vesicles, i.e., a bilayer thickness electron density profile, that takes into account the n-component volume-fraction weighted form factors and size distribution of the DPPC vesicle population in solution. Note: For visualization purposes only, the I(s) axis has been arbitrarily scaled in the primary data display (the downloadable .dat and additional files located in the full-entry zip archive are not scaled accordingly). Before 2024 Jan 16 the downloadable "curve (dat)" was mistakenly sourced from a different dataset although the .dat located under "additional_files" in the full-entry zip archive was correct.

1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC)
Mol. type   Other
Olig. state   Monomer
Mon. MW   0.7 kDa
Chemical formula