Roh Kyung-Ho, Yoshida Mutsumi, Lahann Joerg
Macromolecular Science and Engineering Center, Department of Chemical Engineering, The University of Michigan, Ann Arbor, Michigan 48109, USA.
Langmuir. 2007 May 8;23(10):5683-8. doi: 10.1021/la062274r.
Electrified co-jetting of two aqueous polymer solutions followed by a thermal cross-linking step was used to create water-stable biphasic nanocolloids. For this purpose, aqueous solution mixtures of poly(acrylamide-co-acrylic acid) and poly(acrylic acid) were employed as jetting solutions. When the biphasic nanocolloids created by side-by-side electrified co-jetting were thermally treated, a cross-linking reaction occurred between amide groups and carboxylic groups to form stable imide groups. Infrared spectroscopy was employed to monitor the reaction. The quality and the integrity of the resulting biphasic nanocolloids were confirmed by confocal laser scanning microscopy, flow cytometry analysis, and dynamic light scattering. Selective encapsulation of two biomolecules in each phase of the biphasic colloids was maintained even after thermal reaction and suspension in aqueous environment. Well-dispersed spherical colloids with stable dye loadings in each hemisphere were kept intact without aggregation or dissolution for several weeks. Finally, biphasic nanocolloids were selectively surface-modified with a biotin-dextran resulting in water-stable particles to ensure binding of proteins only to a single hemisphere.
通过对两种聚合物水溶液进行电辅助共喷射，随后进行热交联步骤，制备了水稳定的双相纳米胶体。为此，使用了聚丙烯酰胺-丙烯酸共聚物和聚丙烯酸的水溶液混合物作为喷射溶液。当通过并排电辅助共喷射制备的双相纳米胶体进行热处理时，酰胺基团和羧基之间发生交联反应，形成稳定的酰亚胺基团。采用红外光谱监测该反应。通过共聚焦激光扫描显微镜、流式细胞术分析和动态光散射确认了所得双相纳米胶体的质量和完整性。即使在热反应后并悬浮于水环境中，双相胶体各相中两种生物分子的选择性包封仍得以保持。在每个半球中具有稳定染料负载的分散良好的球形胶体保持完整，数周内不发生聚集或溶解。最后，用生物素-葡聚糖对双相纳米胶体进行选择性表面修饰，得到水稳定的颗粒，以确保蛋白质仅与单个半球结合。
