Matejícek Pavel, Uchman Mariusz, Lokajova Jana, Stepanek Miroslav, Prochazka Karel, Spírkova Milena
Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Albertov 2030, 128 40 Prague 2, Czech Republic.
J Phys Chem B. 2007 Jul 26;111(29):8394-401. doi: 10.1021/jp0685075. Epub 2007 Apr 7.
The size and structural changes of nanoparticles formed after the addition of poly(2-vinylpyridine), PVP, to block copolymer micelles of polystyrene-block-poly(methacrylic acid), PS-PMA, were studied by light scattering and atomic force microscopy. Due to the strong hydrogen bonding between PVP and PMA segments, complex structures based on the core/shell micelles form in mixed selective solvents. As proven by a combination of light scattering and atomic force microscopy, individual PS-PMA micelles are "glued" together by PVP chains. The dialysis against solvents with a high content of water results in transient increase in polydispersity and turbidity of originally clear solutions. However, the precipitated polymer material dissolves in basic buffers and stable soluble nanoparticles reform in aqueous media. The behavior of their solutions was studied in a broad pH range by light scattering, atomic force microscopy and capillary zone electrophoresis.
通过光散射和原子力显微镜研究了在聚苯乙烯-嵌段-聚(甲基丙烯酸)(PS-PMA)嵌段共聚物胶束中加入聚(2-乙烯基吡啶)(PVP)后形成的纳米颗粒的尺寸和结构变化。由于PVP与PMA链段之间存在强氢键,在混合选择性溶剂中会形成基于核/壳胶束的复杂结构。光散射和原子力显微镜相结合的结果表明,单个PS-PMA胶束通过PVP链“粘合”在一起。用高含水量的溶剂进行透析会导致原本澄清的溶液的多分散性和浊度暂时增加。然而,沉淀的聚合物材料可溶解于碱性缓冲液中,并在水性介质中重新形成稳定的可溶性纳米颗粒。通过光散射、原子力显微镜和毛细管区带电泳在较宽的pH范围内研究了它们溶液的行为。