title: Next-Generation Polymer Shells for Inorganic Nanoparticles are Highly Compact, Ultra-Dense, and Long-Lasting Cyclic Brushes.
abstract: Cyclic poly-2-ethyl-2-oxazoline (PEOXA) ligands for superparamagnetic Fe3O4nanoparticles (NPs) generate ultra-dense and highly compact shells, providing enhanced colloidal stability and bio-inertness in physiological media. When linear brush shells fail in providing colloidal stabilization to NPs, the cyclic ones assure long lasting dispersions. While the thermally induced dehydration of linear PEOXA shells cause irreversible aggregation of the NPs, the collapse and subsequent rehydration of similarly grafted cyclic brushes allow the full recovery of individually dispersed NPs. Although linear ligands are densely grafted onto Fe3O4cores, a small plasma protein such as bovine serum albumin (BSA) still physisorbs within their shells. In contrast, the impenetrable entropic shield provided by cyclic brushes efficiently prevents nonspecific interaction with proteins.
authors.affiliation: Laboratory for Surface Science and Technology, Department of Materials, ETH Zürich, Zürich, Switzerland.|Cartilage Engineering and Regeneration Laboratory, ETH Zürich, Department of Health Sciences and Technology, ETH Zürich, Zürich, Switzerland.
authors.forename: Giulia
authors.initials: G
authors.lastname: Morgese
authors.affiliation: Institute for Biologically Inspired Materials, Department of Nanobiotechnology, University of Natural Resources and Life Sciences, Vienna, Austria.
authors.forename: Behzad
authors.initials: B
authors.lastname: Shirmardi Shaghasemi
authors.affiliation: Dipartimento di Scienze Chimiche, Università degli Studi di Padova, Padova, Italy.
authors.forename: Valerio
authors.initials: V
authors.lastname: Causin
authors.affiliation: Cartilage Engineering and Regeneration Laboratory, ETH Zürich, Department of Health Sciences and Technology, ETH Zürich, Zürich, Switzerland.
authors.forename: Marcy
authors.initials: M
authors.lastname: Zenobi-Wong
authors.affiliation: Laboratory for Surface Science and Technology, Department of Materials, ETH Zürich, Zürich, Switzerland.
authors.forename: Shivaprakash N
authors.initials: SN
authors.lastname: Ramakrishna
authors.affiliation: Institute for Biologically Inspired Materials, Department of Nanobiotechnology, University of Natural Resources and Life Sciences, Vienna, Austria.
authors.forename: Erik
authors.initials: E
authors.lastname: Reimhult
authors.affiliation: Laboratory for Surface Science and Technology, Department of Materials, ETH Zürich, Zürich, Switzerland.
authors.forename: Edmondo M
authors.initials: EM
authors.lastname: Benetti
keywords: core-shell nanoparticles; polymer brushes; polymer topology; polyoxazolines; surface functionalization