| 초록 |
pH-sensitive liposomes were prepared by stabilizing dioleoylphosphatidyl ethanolamine(DOPE) using 2-hexadecyloxy cinnamic acid (2-CA) and acidic protenoid(AP). Dry films for liposomes were consist of 14mg DOPE mixed with various concentration of 2-CA. Compound of DOPE and 2-CA with the molar ratio of 4.5:1, 4:1, 3:1, 2:3.5, 1:4.5 (mol/mol) was hydrated in 2ml HEPES buffer solution containing hydrophilic dye, (5(6)-carboxyfluorescein (CF, 100mM), and deoxycholate (DOC) which concentration was 0.09%, respectively. When the molar ratio of DOPE to 2-CA was 1:4, 1:4.5, fluorescence quenching of CF was not determined, but when that of DOPE to 2-CA was 3:1, 2:3.5, 1:4.5, the fluorescence quenching of CF was increased more than 60%. With the liposomes composed of DOPE/2-CA, almost 12% release of CF was observed at pH 9 and pH 11 in 5min. Especially, the release of CF from DOPE/2-CA liposome was remarkably increased to 26% at pH 7 in 5min. |
