| Abstract: | A carbonyl hemoglobin (HbCO) solution was stirred with a mixed powder of polymerizable 1,2-bis(2,4-octadecadienoyl)-sn-glycero-3-phosphocholine (DODPC), cholesterol and stearic acid (7/7/2 by mol). The mixture was extruded through polycarbonate membrane filters (final pore size = 0.2 μm Ø). The average diameter of the resulting vesicles was 203 ± 39 nm. The Hb]/Lipid] ratio (the weight ratio of Hb in vesicle to lipid) increased with the Hb concentration, and decreased with the NaCl concentration. A maximum Hb]/lipid] ratio was observed at pH 6.9, which was the same as the isoelectric point of Hb. The vesicles were stabilized by γ-irradiation (60Co) because the bilayer lipids bound each other to yield polyphospholipids. Denaturation of Hb by γ-irradiation was not detected. These polyphospholipid vesicles encapsulating Hb were stable even against the freeze–thaw cycles and the freeze-drying procedure. |
