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为了研究对温度敏感的双亲性共聚物包覆的脂质体的温控释放行为，合成了Ｎ异丙基丙烯酰胺（ＮＩＰＡＭ）和丙烯酸十八酯（ＯＤＡ）的共聚物．利用荧光探针法研究了共聚物水溶液随温度升高时出现的ＬＣＳＴ（ｌｏｗｅｒｃｒｉｔｉｃａｌｓｏｌｕｔｉｏｎｔｅｍｐｅｒａｔｕｒｅ）现象，表明该高分子在温度升高到３０℃以上时存在着明显的相分离行为．以５（６）羧基荧光素（５（６）ＣＦ）为标记物，研究了高分子包覆的小单层脂质体（ｓｍａｌｕｎｉｌａｍｅｌａｒｖｅｓｉｃｌｅｓ）的释放行为．发现在温度低于３０℃时，５（６）ＣＦ的释放百分率比未包覆高分子的脂质体要低；而当温度升高到３０℃以上时，其释放百分率明显提高．这种温控释放行为和包覆在脂质体上的高分子在其ＬＣＳＴ时存在的相分离行为有关．进一步利用荧光偏振法研究了脂质体膜在包覆高分子后的流动性变化，发现：在温度低于３０℃时，其流动性随温度升高而增大；而在温度高于３０℃时，脂质体膜流动性随温度升高而降低，进一步证实了高分子在其ＬＣＳＴ以上时对脂质体膜的破坏作用
In order to study the temperature-controlled release behavior of temperature-sensitive amphiphilic copolymer-coated liposomes, a copolymer of N-isopropyl acrylamide (NIPAM) and octadecyl acrylate (ODA) was synthesized. The LCST (lowercritical liquid chromatography) phenomenon of copolymer aqueous solution with increasing temperature was studied by fluorescence probe method, which indicated that the polymer had obvious phase separation behavior when the temperature was increased above 30 ℃. The release behavior of polymer-coated smaLnilamelarvesicles was investigated with 5 (6) -carboxyfluorescein (5 (6) CF). It was found that the release percentage of 5 (6) CF was lower than that of uncoated polymer when the temperature was lower than 30 ℃. When the temperature was above 30 ℃, the release percentage of 5 (6) CF significantly increased. This temperature-controlled release behavior is related to the phase separation behavior of the polymer-coated liposomes at their LCST. Fluorescence polarization method was used to study the change of fluidity of the liposome membrane coated with polymer. It was found that the fluidity of the liposome membrane increased with the increase of temperature when the temperature was lower than 30 ℃. When the temperature was higher than 30 ℃, , The liposome membrane fluidity decreases with increasing temperature, further confirming the destruction of the liposome membrane by the polymer above its LCST