2.5D Hierarchical Structuring of Nanocomposite Hydrogel Films Containing Cellulose Nanocrystals

Research output: Contribution to journalArticleScientificpeer-review

Researchers

  • Kevin J. De France
  • Mouhanad Babi
  • Jaana Vapaavuori

  • Todd Hoare
  • Jose Moran-Mirabal
  • Emily D. Cranston

Research units

  • McMaster University
  • University of Montreal
  • University of British Columbia

Abstract

Although two-dimensional hydrogel thin films have been applied across many biomedical applications, creating higher dimensionality structured hydrogel interfaces would enable potentially improved and more biomimetic hydrogel performance in biosensing, bioseparations, tissue engineering, drug delivery, and wound healing applications. Herein, we present a new and simple approach to control the structure of hydrogel thin films in 2.5D. Hybrid suspensions containing cellulose nanocrystals (CNCs) and aldehyde- or hydrazide-functionalized poly(oligoethylene glycol methacrylate) (POEGMA) were spin-coated onto prestressed polystyrene substrates to form cross-linked hydrogel thin films. The films were then structured via thermal shrinking, with control over the direction of shrinking leading to the formation of biaxial, uniaxial, or hierarchical wrinkles. Notably, POEGMA-only hydrogel thin films (without CNCs) did not form uniform wrinkles due to partial dewetting from the substrate during shrinking. Topographical feature sizes of CNC POEGMA films could be tuned across 2 orders of magnitude (from 300 nm to 20 kern) by varying the POEGMA concentration, the length of poly(ethylene glycol) side chains in the polymer, and/or the overall film thickness. Furthermore, by employing adhesive masks during the spin-coating process, structured films with gradient wrinkle sizes can be fabricated. This precise control over both wrinkle size and wrinkle topography adds a level of functionality that to date has been lacking in conventional hydrogel networks.

Details

Original languageEnglish
Pages (from-to)6325-6335
Number of pages11
JournalACS Applied Materials and Interfaces
Volume11
Issue number6
Publication statusPublished - 1 Jan 2019
MoE publication typeA1 Journal article-refereed

    Research areas

  • cellulose nanocrystals, structured hydrogels, thin-film hydrogels, wrinkling, hierarchical wrinkles, POLY(ETHYLENE GLYCOL), MECHANICAL-PROPERTIES, WRINKLING PATTERNS, THIN-FILM, IN-SITU, FABRICATION, SCALE, ADHESION, GROWTH, CELLS

ID: 32394039