title: Biomembrane sensitivity to structural changes in bound polymers.
abstract: Anionic liposomes containing a 4:1 molar ratio of neutral to anionic phospholipids were treated with an excess of five zwitterionic polymers differing only in the spacer length separating their cationic and anionic moieties. Although the polymers do not disrupt the structural integrity of the liposomes, they can induce spacer-dependent molecular rearrangements within the liposomes. Thus, the following were observed: spacer length = 1, no binding to the liposomes; spacer length = 2, adsorption to the liposomes, but no molecular rearrangement; spacer length = 3, lateral lipid segregation but little or no flip-flop; spacer length = 4 or 5, lateral lipid segregation and flip-flop. These diverse behaviors are relevant to the use of biomedical formulations where polyelectrolytes play a role.
authors.affiliation: Department of Chemistry, M.V. Lomonosov Moscow State University, Leninskie Gory, Moscow, RF.
authors.forename: Alexander A
authors.initials: AA
authors.lastname: Yaroslavov
authors.forename: Tatiana A
authors.initials: TA
authors.lastname: Sitnikova
authors.forename: Anna A
authors.initials: AA
authors.lastname: Rakhnyanskaya
authors.forename: Ekaterina G
authors.initials: EG
authors.lastname: Yaroslavova
authors.forename: Dmitry A
authors.initials: DA
authors.lastname: Davydov
authors.forename: Tatiana V
authors.initials: TV
authors.lastname: Burova
authors.forename: Valery Ya
authors.initials: VY
authors.lastname: Grinberg
authors.forename: Lei
authors.initials: L
authors.lastname: Shi
authors.forename: Fredric M
authors.initials: FM
authors.lastname: Menger
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry; D002152:Calorimetry, Differential Scanning; D008051:Lipid Bilayers / Q000737:chemistry; D008081:Liposomes / Q000737:chemistry*; D008958:Models, Molecular; D010713:Phosphatidylcholines / Q000737:chemistry; D010743:Phospholipids / Q000737:chemistry*; D011145:Polyvinyls / Q000737:chemistry; D013050:Spectrometry, Fluorescence
chemical_list: D008051:Lipid Bilayers; D008081:Liposomes; D010713:Phosphatidylcholines; D010743:Phospholipids; D011145:Polyvinyls; C019535:poly(4-vinylpyridine); D015060:1,2-Dipalmitoylphosphatidylcholine; C017251:1,2-oleoylphosphatidylcholine