Synthesis and Properties of Alkyl Phosphorylcholine Amphiphiles with a Linear and an Asymmetrically Branched Alkyl Chain
作者:Eui-Chul Kang、Shingo Kataoka、Kenji Kato
DOI:10.1246/bcsj.78.1558
日期:2005.8
Alkyl phosphorylcholine amphiphiles bearing one linear chain and one asymmetrically branched alkyl chain were successfully synthesized using 2-chloro-2-oxo-1,3,2-dioxaphospholane in tetrahydrofuran or ethyl acetate. 1H and 31P NMR studies revealed that the linear alkyl phosphorylcholines (Cn-PC) provide aqueous micelles in D2O and reverse micelles in CDCl3, while the branched alkyl phosphorylcholines (ISOFOLn-PC) give vesicles in D2O. The critical micelle concentrations (CMCs) of Cn-PC were measured by fluorescence dye solubilization methods: the CMCs of C12-PC, C14-PC, C16-PC, and C18-PC were 1.6, 0.38, 0.16, and 0.11 mM, respectively, in water at 25 °C. The critical association concentrations (CACs) of ISOFOL16-PC, ISOFOL20-PC, and ISOFOL24-PC were 0.068, 0.005, and 0.077 mM, respectively, in water at 25 °C. The vesicle size of ISOFOLn-PC in aqueous solution was measured by the dynamic light scattering method. The mean diameter of ISOFOLn-PC vesicles was approximately 30 nm and the size distribution was relatively monodisperse. The ISOFOLn-PC vesicles formed were colloidally stable in water over the period of several weeks.
成功合成了具有一条直链和一条不对称支链烷基链的烷基膦酰胆碱两亲物,使用2-氯-2-氧代-1,3,2-二氧磷环在四氢呋喃或乙酸乙酯中进行合成。1H和31P核磁共振研究表明,直链烷基膦酰胆碱(Cn-PC)在D2O中提供水溶胶束,在CDCl3中提供反向胶束,而支链烷基膦酰胆碱(ISOFOLn-PC)在D2O中形成囊泡。通过荧光染料溶解方法测定了Cn-PC的临界胶束浓度(CMCs):在25°C的水中,C12-PC、C14-PC、C16-PC和C18-PC的CMCs分别为1.6、0.38、0.16和0.11 mM。在25°C的水中,ISOFOL16-PC、ISOFOL20-PC和ISOFOL24-PC的临界缔合浓度(CACs)分别为0.068、0.005和0.077 mM。通过动态光散射方法测量了ISOFOLn-PC在水溶液中的囊泡大小。ISOFOLn-PC囊泡的平均直径约为30 nm,尺寸分布相对单一。ISOFOLn-PC囊泡在水溶液中形成,具有几周时间的胶体稳定性。