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Updated: Jun 26, 2026

Preparation and Characterization of Nanoliposomes for the Entrapment of Bioactive Hydrophilic Globular Proteins
Published on: August 31, 2019
Molecular umbrella transport: exceptions to the classic size/lipophilicity rule
Mohamed Mehiri1, Wen-Hua Chen, Vaclav Janout
1Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, USA.
Abstract:
The ability of a series of molecular umbrellas, derived from cholic acid, L-lysine, spermidine, and Cascade Blue, to cross fluid liposomal membranes made from 1-palmitoyl-2-oleyol-sn-glycero-3-phosphocholine (POPC)/1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylglycerol (POPG) (95/5, mol/mol) has been determined. In sharp contrast to the classic "size/lipophilicity" rule of membrane transport, those molecular umbrellas that were larger in size and less lipophilic crossed these liposomal membranes more readily. The likely origin for this unusual behavior is briefly discussed.
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