title: Affinity partitioning for membrane purification exploiting the biotin-NeutrAvidin interaction. Model study of mixed liposomes and membranes.
abstract: Biotinylated negatively charged liposomes as well as membranes were affinity partitioned in an aqueous poly(ethylene glycol)-dextran two-phase system using NeutrAvidin conjugated to dextran as affinity ligand. Both liposomes and membranes redistributed from top to bottom phase upon addition of NeutrAvidin-dextran. The presence of 35-60 mM Li2SO4 was necessary both to force the components into the top phase without ligand and for ligand-dependent redistribution into the bottom phase. Attaching biotin via a hexanamidohexanoyl spacer and an increased density of biotin or NeutrAvidin enhanced the affinity separation. The separation conditions in these model experiments provide a basis for affinity partitioning of membranes using other affinity ligands.
mesh_terms: D001360:Avidin / Q000737:chemistry*; D001710:Biotin / Q000737:chemistry*; D002846:Chromatography, Affinity / Q000379:methods*; D008081:Liposomes; D018020:Lithium Compounds / Q000737:chemistry; D008567:Membranes, Artificial; D008956:Models, Chemical; D013431:Sulfates / Q000737:chemistry
chemical_list: D008081:Liposomes; D018020:Lithium Compounds; D008567:Membranes, Artificial; D013431:Sulfates; D001360:Avidin; D001710:Biotin; C054097:lithium sulfate