Physicochemical Studies on the Phospholipid Bilayer Incorporated.
作者:Hideo KANEKO、Naokazu MURAHASHI、Atsushi SASAKI、Harutami YAMADA、Masahiro SAKAGAMI、Masahiro IKEDA
DOI:10.1248/cpb.45.951
日期:——
With the intention of obtaining a novel liposome as a drug carrier able to avoid clearance by the reticuloendothelial system (RES), the authors synthesized two sialoglycolipids, i.e., 2-O-(8-hexadecanoylamino-3, 6-dioxaoctyl)-β-N-acetylneuraminic acid sodium salt (Sia-t-pa) and 2-O-[8-(2-hexadecyloctadecanoylamino)-3, 6-dioxaoctyl]-β-N-acetylneuraminic acid sodium salt (Sia-t-psa) and modified the surface of their liposomal membrane.Sia-t-pa was found to be eluted from the liposomal membrane by serum albumin, whereas Sia-t-psa was not, using the gel filtration method. In order to clarify the reason why there was such a difference between Sia-t-pa and Sia-t-psa, we investigated the properties of the phospholipid bilayer-incorporated sialoglycolipids physicochemically.The effect of the anchor structure of the sialoglycolipids, i.e., single acyl chain (Sia-t-pa) or double acyl chain (Sia-t-psa), on the fluidity and calorimetric properties was noticeably different. It was inferred that the effect was attributable to a difference in the position of the sialoglycolipid incorporated in the bilayer membrane.
为了获得一种新型脂质体作为药物载体,以避免被网状内皮系统(RES)清除,作者合成了两种sialoglycolipids,即:2-O-(8-hexadecanoylamino-3, 6-dioxaoctyl)-β-N-乙酰神经氨酸钠盐(Sia-t-pa)、2-O-(8-hexadecyloctadanoylamino-3, 6-dioxaoctyl)-β-N-acetylneuraminic acid sodium salt (Sia-t-pa)和 2-O-[8-(2-hexadecyloctadanoylamino)-3, 6-dioxaoctyl]-β-N-acetylneuraminic acid sodium salt (Sia-t-psa),并对其脂质体膜表面进行了修饰。使用凝胶过滤法发现,血清白蛋白能从脂质体膜上洗脱 Sia-t-pa,而 Sia-t-psa 却不能。为了弄清 Sia-t-pa 和 Sia-t-psa 之间存在这种差异的原因,我们从理化角度研究了磷脂双分子层包合的硅氧烷糖脂的特性。硅氧烷糖脂的锚结构(即单酰基链(Sia-t-pa)或双酰基链(Sia-t-psa))对流动性和热量特性的影响明显不同。据推断,这种影响可归因于双分子层膜中的酰基糖脂的位置不同。