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Sterol-modified PEG lipids: alteration of the bilayer anchoring moiety has an unexpected effect on liposome circulation.

ABSTRACT: We synthesized and characterized two novel sterol-anchored polyethylene glycols (PEG) as potential alternatives to conventional phosphatidylethanolamine-PEGs. Liposomes containing the dicholesterol anchored PEG at 5 mole percent exhibit canonical PEGgylated-liposome behaviors including retention of encapsulated small molecules, low serum protein adsorption, and reduced cellular uptake yet they do not exhibit long circulation.

SUBMITTER: Dolor A

PROVIDER: S-EPMC6764448 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Sterol-modified PEG lipids: alteration of the bilayer anchoring moiety has an unexpected effect on liposome circulation.

Dolor Aaron A Kierstead Paul P Dai Zhipeng Z Szoka Francis C FC

Chemical communications (Cambridge, England) 20181005 84

We synthesized and characterized two novel sterol-anchored polyethylene glycols (PEG) as potential alternatives to conventional phosphatidylethanolamine-PEGs. Liposomes containing the dicholesterol anchored PEG at 5 mole percent exhibit canonical PEGgylated-liposome behaviors including retention of encapsulated small molecules, low serum protein adsorption, and reduced cellular uptake yet they do not exhibit long circulation. ...[more]

PMID: 30288531

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