title: Interactive transport of guanidinylated poly(propylene imine)-based dendrimers through liposomal and cellular membranes.
abstract: The ability of guanidinylated poly(propylene imine) dendrimers to translocate across lipid bilayers was assessed by employing either a model phosphate-bearing liposomal membrane system or A549 human lung carcinoma cells. Two dendrimer generations, differing in the number of surface guanidinium groups, were employed, while surface acetylation or the use of spacers affected the binding of the guanidinium group to the phosphate moiety and finally the transport efficiency. Following adhesion of dendrimers with liposomes, fusion or transport occurred. Transport through the liposomal bilayer was observed at low guanidinium/phosphate molar ratios, and was enhanced when the bilayer was in the liquid-crystalline phase. For effective transport through the liposomal membrane, an optimum balance between the binding strength and the degree of hydrophobicity of the guanidinylated dendrimer is required. In experiments performed in vitro with cells, efficient penetration and internalization in subcellular organelles and cytosol was observed.
authors.affiliation: Institute of Physical Chemistry, NCSR Demokritos, 15310 Aghia Paraskevi, Attiki, Greece.
authors.forename: Ioannis
authors.initials: I
authors.lastname: Tsogas
authors.forename: Zili
authors.initials: Z
authors.lastname: Sideratou
authors.forename: Dimitris
authors.initials: D
authors.lastname: Tsiourvas
authors.forename: Theodossis A
authors.initials: TA
authors.lastname: Theodossiou
authors.forename: Constantinos M
authors.initials: CM
authors.lastname: Paleos
mesh_terms: D001665:Binding Sites; D001692:Biological Transport; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism*; D002470:Cell Survival; D003600:Cytosol / Q000737:chemistry / Q000378:metabolism; D050091:Dendrimers / Q000138:chemical synthesis* / Q000378:metabolism*; D019791:Guanidine / Q000031:analogs & derivatives*; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D008081:Liposomes / Q000737:chemistry / Q000378:metabolism*; D008561:Membrane Fusion / Q000502:physiology; D018625:Microscopy, Atomic Force; D008856:Microscopy, Fluorescence; D015388:Organelles / Q000737:chemistry / Q000378:metabolism; D010710:Phosphates / Q000737:chemistry; D011126:Polypropylenes / Q000737:chemistry*; D013347:Subcellular Fractions / Q000737:chemistry / Q000378:metabolism; D014407:Tumor Cells, Cultured
chemical_list: D050091:Dendrimers; D008081:Liposomes; D010710:Phosphates; D011126:Polypropylenes; C443641:poly(propyleneimine); D019791:Guanidine