Related Experiment Video
Updated: Aug 29, 2025

Contrast-Matching Detergent in Small-Angle Neutron Scattering Experiments for Membrane Protein Structural Analysis and Ab Initio Modeling
Published on: October 21, 2018
The non-Newtonian behavior of detergents during concentration is increased by macromolecules, in trans, and results
Alexia Gobet1, Veronica Zampieri2, Sandrine Magnard1
1Molecular Microbiology and Structural Biochemistry, UMR5086 CNRS University lyon1, 7 passage du vercors, 69007, Lyon, France.
Abstract:
Concentration of pure membrane proteins in detergent solution results in detergent concentration, albeit in unknown amounts. This phenomenon is observed in every lab working on membrane proteins, but has seldom been investigated. In this study, we explored the behavior of detergents mixed with membrane proteins during the step of sample concentration using centrifugal devices. We show that detergent over-concentrate with the presence of polymers, typically membrane or soluble proteins but also polysaccharides. The over-concentration of detergents depends on centrifugal force applied to the device. With the use of a specific dye, we observed the formation of a mesh on the concentrator device. Importantly, reducing the centrifugal speed allows to reduce the concentration of detergents when mixed to macromolecules, as tested with 3 different membrane proteins. All together, these results highlight the non-Newtonian behavior of detergents and provides a solid framework to investigators to improve drastically biochemical and structural studies of membrane proteins.
Related Concept Videos
Solubility
A solution is a homogeneous mixture composed of a solvent, the major component, and a solute, the minor component. The physical state of a solution—solid, liquid, or gas—is typically the same as that of the solvent. Solute concentrations are often described with qualitative terms such as dilute (of relatively low concentration) and concentrated (of relatively high concentration).
In a solution, the solute particles (molecules,...
Detergent Purification of Membrane Proteins
Colloids
Theories of Dissolution: The Danckwerts' Model and Interfacial Barrier Model
Colloidal precipitates
Solution Equilibrium and Saturation

