Georgieva Radostina, Moya Sergio, Donath Edwin, Bäumler Hans
Institute of Transfusion Medicine, Medical Faculty, Charité, Humboldt-University Berlin, D-10098 Berlin, Germany.
Langmuir. 2004 Mar 2;20(5):1895-900. doi: 10.1021/la035779f.
The permeability of ions and small polar molecules through polyelectrolyte multilayer capsules templated on red blood cells was studied by means of confocal microscopy and electrorotation. Capsules were obtained by removing the cell after polyelectrolyte multilayer formation by means of NaOCl treatment. This procedure results in cross-linking of poly(allylamine hydrochloride) (PAH) molecules and destroying poly(styrene sulfonate) (PSS) within the multilayer. Capsules are obtained being remarkably different from layer-by-layer (LbL) capsules. These capsules are rather permeable for low as well as for high molecular weight species. However, upon adsorption of extra polyelectrolyte layers the permeability decreased remarkably. The assembly of six supplementary layers of PAH and PSS rendered the capsule almost impermeable for fluorescein. Resealing by supplementary layers is a potential means for filling and release control. By means of electrorotation measurements, it was shown that the capsule walls obtained isolating properties in electrolyte solutions. Conclusions are drawn concerning the mechanism of permeability through cell templated polyelectrolyte multilayer capsules.
通过共聚焦显微镜和电旋转技术研究了以红细胞为模板的聚电解质多层胶囊对离子和小极性分子的渗透性。通过用次氯酸钠处理在聚电解质多层形成后去除细胞来获得胶囊。该过程导致聚（烯丙胺盐酸盐）（PAH）分子交联并破坏多层内的聚（苯乙烯磺酸盐）（PSS）。获得的胶囊与逐层（LbL）胶囊有显著不同。这些胶囊对低分子量和高分子量物质都具有相当高的渗透性。然而，在吸附额外的聚电解质层后，渗透性显著降低。PAH和PSS的六个补充层的组装使胶囊对荧光素几乎不可渗透。通过补充层重新密封是一种用于填充和释放控制的潜在手段。通过电旋转测量表明，获得的胶囊壁在电解质溶液中具有隔离特性。得出了关于通过细胞模板化聚电解质多层胶囊的渗透机制的结论。
