Foster E Johan, Berda Erik B, Meijer E W
Institute for Complex Molecular Systems and Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
J Am Chem Soc. 2009 May 27;131(20):6964-6. doi: 10.1021/ja901687d.
We present an elegant approach for fabricating polymeric nanoparticles via the reversible noncovalent intramolecular cross-linking of single polymer chains. By protecting the well-studied 2-ureido-pyrimidinone moiety with an o-nitrobenzyl group, we have introduced a latent quadruple hydrogen bonding motif. Incorporating this group into linear poly(norbornenes) creates a class of supramolecular materials that can be readily dissolved and subsequently cross-linked upon irradiation with UV light, eliminating the need for selective solvent techniques. This is a facile method for producing well-defined particles with narrow polydispersity as confirmed by atomic force microscopy. By virtue of the nature of the intramolecular cross-linking (supramolecular interactions of pendant groups), these metastable nanoparticles are akin to folded biomacromolecules, representing the first step in linking synthetic polymers and self-folded biopolymers.
我们提出了一种通过单聚合物链的可逆非共价分子内交联来制备聚合物纳米颗粒的巧妙方法。通过用邻硝基苄基保护经过充分研究的2-脲基嘧啶酮部分，我们引入了一种潜在的四重氢键基序。将该基团引入线性聚降冰片烯中，形成了一类超分子材料，这类材料可以很容易地溶解，随后在紫外光照射下交联，无需选择性溶剂技术。如原子力显微镜所证实的，这是一种制备具有窄多分散性的明确颗粒的简便方法。由于分子内交联的性质（侧基的超分子相互作用），这些亚稳态纳米颗粒类似于折叠的生物大分子，代表了连接合成聚合物和自折叠生物聚合物的第一步。
