| Title | Poly(ethylene glycol) amphiphile adsorption and liposome partition |
| Publication Type | Journal Article |
| Year of Publication | 1996 |
| Authors | VanAlstine, JM, Malmsten, M, Brooks, DE |
| Journal | Journal of Chromatography B-Biomedical Applications |
| Volume | 680 |
| Pagination | 145-155 |
| Date Published | May |
| Type of Article | Proceedings Paper |
| ISBN Number | 0378-4347 |
| Keywords | ADSORPTION, AQUEOUS 2-PHASE SYSTEMS, BEHAVIOR, CELL-SEPARATION, critical micelle concentration, ellipsometry, HYDROPHOBIC AFFINITY PARTITION, LIPOSOMES, partitioning, PHASE SYSTEMS, poly(ethylene glycol) (PEG), polymer, PROTEINS, SURFACE-PROPERTIES, WATER-INTERFACE |
| Abstract | Surface localized poly(ethylene glycol) (PEG) amphiphiles of type C-16:0-EO(151) and C-18:2-EO(1.51) were studied via ellipsometry at macroscopic, hat methylated silica (MeSi), phosphatidic acid (PA), and phosphatidylcholine (PC) surfaces. At these surfaces the amphiphiles adsorb similarly, in a non-cooperative manner, achieving a plateau (approximate to 0.1 PEG chains/nm(2)) well below amphiphile critical micelle concentration (CMC). The resultant PEG-enriched layers were 10-15 nm thick, with a polymer concentration (approximate to 0.07 g/cm(3)) greater than the PEG-enriched phase of many dextran, PEG aqueous two-phase systems. PEG-amphiphile adsorption (mg/m(2)) at hydrophobic and phospholipid flat surfaces correlated with changes in the partition (log K) of PC liposomes in such two-phase systems. PEG-amphiphile adsorption at macroscopic surfaces appears to represent a balance between hydrophobic attraction and repulsive intra-chain interactions which promote chain elongation normal to the surface. |
| URL | <Go to ISI>://A1996UQ82100016 |
