Interactions of adriamycin, cytochrome c, and serum albumin with lipid monolayers containing poly(ethylene glycol)-ceramide.
Poly(ethylene glycol)(2000)C(20)ceramide (PEG-Cer) containing monolayers at an air/water interface were characterized by measuring their surface pressure versus area/molecule (pi-A) and surface potential versus area/molecule (Delta V-A) isotherms. The behavior of pi-A as well as Delta V versus lipid density (Delta V-n) and Delta V-pi isotherms for PEG-Cer are in keeping with two transitions of the lipopolymer, starting at pi approximately equal to 9 and 21 mN/m. We also investigated the effects of PEG-Cer on the binding of adriamycin, cytochrome c and bovine serum albumin to monolayers containing varying mole fractions X of PEG-Cer. PEG-Cer impedes the penetration of these ligands into lipid monolayers with similar effects at both X = 0.04 and 0.08. This effect of PEG-Cer depends on the conformation of the lipopolymer and the interactions between the lipid surface and the surface-interacting molecule as well as the size of the latter.
Helsinki Biophysics and Biomembrane Group, Institute of Biomedicine, University of Helsinki, FIN-00014 Helsinki, Finland.
Hongxia
H
Zhao
Patricia M
PM
Dubielecka
Tim
T
Söderlund
Paavo K J
PK
Kinnunen
D000388:Air; D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000737:chemistry / Q000378:metabolism; D055592:Biophysical Phenomena; D001703:Biophysics; D002518:Ceramides / Q000737:chemistry*; D002645:Chickens; D003574:Cytochrome c Group / Q000737:chemistry / Q000378:metabolism*; D004317:Doxorubicin / Q000737:chemistry / Q000378:metabolism*; D006736:Horses; D008024:Ligands; D008055:Lipids / Q000737:chemistry*; D008564:Membrane Potentials; D008856:Microscopy, Fluorescence; D010714:Phosphatidylethanolamines / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry*; D012709:Serum Albumin / Q000737:chemistry / Q000378:metabolism*; D013696:Temperature; D014867:Water
D000903:Antibiotics, Antineoplastic; D002518:Ceramides; D003574:Cytochrome c Group; D008024:Ligands; D008055:Lipids; D010714:Phosphatidylethanolamines; D012709:Serum Albumin; D014867:Water; C057561:1-palmitoyl-2-oleoylphosphatidylethanolamine; D011092:Polyethylene Glycols; D004317:Doxorubicin