Postfabrication Tethering of Molecular Gradients on Aligned Nanofibers of Functional Poly(ε-caprolactone)s

Biomacromolecules. 2019 Dec 9;20(12):4494-4501. doi: 10.1021/acs.biomac.9b01264. Epub 2019 Nov 26.

Abstract

Substrates with combinations of topographical and biochemical cues are highly useful for a number of fundamental biological investigations. Tethered molecular concentration gradients in particular are highly desired for a number of biomedical applications including cell migration. Herein, we report a versatile method for the fabrication of aligned nanofiber substrates with a tunable concentration gradient along the fiber direction. 4-Dibenzocyclooctynol (DIBO) was used as an initiator for the ring-opening copolymerization of ε-caprolactone (εCL) and allyl-functionalized ε-caprolactone (AεPCL), which yielded a well-defined polymer with orthogonal functional handles. These materials were fabricated into aligned nanofiber substrates via touch-spinning. Fibers were modified post-spinning with a concentration gradient of fluorescently labeled dye via a light activated thiol-ene reaction through a photomask. As a demonstration, the cell adhesive peptide RGD was chemically tethered to the fiber surface at a second functionalization site via strain-promoted azide-alkyne cycloaddition (SPAAC). This novel approach affords fabrication of dual functional nanofiber substrates.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Cycloaddition Reaction
  • Nanofibers / chemistry*
  • Oligopeptides / chemistry*
  • Polyesters / chemical synthesis*
  • Polyesters / chemistry*

Substances

  • Oligopeptides
  • Polyesters
  • polycaprolactone
  • arginyl-glycyl-aspartic acid