Abstract:
:Interactions between the graft copolymer poly(L-lysine)-g-poly(ethylene glycol), PLL-g-PEG, and two kinds of surface-supported lipidic systems (supported phospholipid bilayers and supported vesicular layers) were investigated by a combination of microscopic and spectroscopic techniques. It was found that the application of the copolymer to zwitterionic or negatively charged supported bilayers in a buffer of low ionic strength led to their decomposition, with the resulting formation of free copolymer-lipid complexes. The same copolymer had no destructive effect on a supported vesicular layer made up of vesicles of identical composition. A comparison between poly(L-lysine), which did not induce decomposition of supported bilayers, and PLL-g-PEG copolymers with various amounts of PEG side chains per backbone lysine unit, suggested that steric repulsion between the PEG chains that developed upon adsorption of the polymer to the nearly planar surface of a supported phospholipid bilayer (SPB) was one of the factors responsible for the destruction of the SPBs by the copolymer. Other factors included the ionic strength of the buffer used and the quality of the bilayers, pointing toward the important role defects present in the SPBs play in the decomposition process.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Rossetti FF,Reviakine I,Csúcs G,Assi F,Vörös J,Textor Mdoi
10.1529/biophysj.104.041780subject
Has Abstractpub_date
2004-09-01 00:00:00pages
1711-21issue
3eissn
0006-3495issn
1542-0086pii
S0006-3495(04)73652-8journal_volume
87pub_type
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