In Situ Cross-Linked Nanofibers by Aqueous Electrospinning of Selenol-Functionalized Poly(2-oxazoline)s

Poly(2-oxazoline)-based biomaterials have shown significant potential for various applications in the past decade. Herein, we present a methodology for the design of degradable diselenide-cross-linked nanofibers by aqueous electrospinning of selenol (SeH)-modified poly(2-ethyl-2-oxazoline) (PEtOx). The selenol groups have been introduced into PEtOx by reacting partially hydrolyzed PEtOx (poly(2-ethyl-2-oxazoline-)-co-ethylenimine (PEtOx-EI)) with γ-butyroselenolactone, whereby ring-opening upon reaction with the secondary amine groups in the polymer backbone yields selenol side chains. Subsequent aqueous electrospinning of the selenol-containing PEtOx was found to lead to in situ cross-linked water-stable nanofibers, ascribed to the formation of diselenide cross-links. The effects of changes in the experimental parameters and the influence of the selenium content on the electrospinning process were investigated in detail. Dynamic exchange between the remaining free SeH groups and diselenide bonds formed u...