title: Metastable supramolecular polymer nanoparticles via intramolecular collapse of single polymer chains.
abstract: 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.
authors.affiliation: 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.
authors.forename: E Johan
authors.initials: EJ
authors.lastname: Foster
authors.forename: Erik B
authors.initials: EB
authors.lastname: Berda
authors.forename: E W
authors.initials: EW
authors.lastname: Meijer