Adsorption of neutral polymers on negatively charged liposomes. A novel quantitative method to measure the rate of polymer adsorption on the liposomal surface
Adsorption of neutral polymers on negatively charged liposomes. A novel quantitative method to measure the rate of polymer adsorption on the liposomal surface
复制标题
带负电荷的脂质体上中性聚合物的吸附。
DOI：
--
复制
发表时间：
2001
期刊：
影响因子：
--
通讯作者：
I. Erös
中科院分区：
文献类型：
--
作者：
György Dékány;I. Csóka;I. Erös
本文研究了两种中性高分子[聚乙烯吡咯烷酮（PVA）和聚乙烯醇（PVA）]在由大豆卵磷脂/磷酸双十六烷基酯/胆固醇（摩尔比）为25：2：3组成的带负电荷脂质体上的吸附。通过测定聚合物的平衡体积浓度来测量吸附。使用盐酸鱼精蛋白使脂质体与吸附在其表面上的聚合物聚集，并促进其从平衡本体溶液中分离。在PVA的情况下，用特定试剂进行定量吸附测量是可能的。在25 ± 0.2 °C下记录吸附等温线。得出的结论是，吸附和未吸附的PVA分子处于平衡状态，即使在低聚合物/水的比例。动态激光光散射、X射线衍射和热活性监测实验证实了上述结果。
Abstract We studied the adsorption of two neutral polymers [poly(vinyl pyrrolidone) and poly(vinyl alcohol) (PVA)] on negatively charged liposomes composed of 25:2:3 (molar ratio) soy lecithin/dicetyl phosphate/cholesterol.The liposomes were prepared in buffered solution at pH 7.4 and were mixed with the solution of the polymers in the desired polymer/lipid ratios. Adsorption was measured by determination of the equilibrium bulk concentration of the polymer. Protamine hydrochloride was used to aggregate the liposomes with polymers adsorbed on their surface and to facilitate their separation from the equilibrium bulk solution. In the case of PVA, quantitative adsorption measurements with a specific reagent were possible. Adsorption isotherms were recorded at 25 ± 0.2 °C. It was concluded that adsorbed and nonadsorbed PVA molecules are in equilibrium even at low polymer/lipide ratios. The results were confirmed by dynamic laser light scattering, X-ray diffraction and thermal activity monitoring experiments.