Lipid Corralling and Poloxamer Squeeze-Out in Membranes

Guohui Wu, Jaroslaw Majewski, Canay Ege, Kristian Kjaer, Markus Jan Weygand, Ka Yee C. Lee
2004 Physical Review Letters  
Using x-ray scattering measurements we have quantitatively determined the effect of poloxamer 188 (P188), a polymer known to seal damaged membranes, on the structure of lipid monolayers. P188 selectively inserts into low lipid-density regions of the membrane and "corrals" lipid molecules to pack tightly, leading to unexpected Bragg peaks at low nominal lipid density and inducing lipid/poloxamer phase separation. At tighter lipid packing, the once inserted P188 is squeezed out, allowing the
more » ... amer to gracefully exit when the membrane integrity is restored.
doi:10.1103/physrevlett.93.028101 pmid:15323953 fatcat:dnqwfib6pzasjntfsj3smn2mvm