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Mechanical characterization of sequentially layered photo-clickable thiol-ene hydrogels



Aaron Aziz, Joseph Wahlquist, Aaron Sollner, Virginia L. Ferguson, Frank W. DelRio, Stephanie Bryant


Multi-layer hydrogels formed from crosslinked poly(ethylene glycol) (PEG) have shown promise for applications in tissue engineering ranging from vasculature to musculoskeletal tissues. The objective of this work was to characterize the interface resulting from sequentially polymerized layers of PEG precursor solutions and the impact that processing has on macroscopic properties. We chose a simple bilayer PEG hydrogel formed from photo-clickable thiol-ene macromolecular monomers. This reaction scheme was chosen for its highly specific and efficient reaction that leads to homogeneous polymer networks and the rapid gelation times afforded by light-activation. This study investigates bilayer hydrogels and (a) the effects of monomer transport between the two layers as a function of processing conditions on interface thickness and bulk mechanical properties and (b) the local mechanical properties and strain transfer across the interface when each hydrogel layer is formed with different mechanical properties. The latter is important for applications where mechanical forces are applied to multi-layer hydrogels. Overall, this study aims to provide insight into how processing influences the formation of the interface and the properties of the interface and ultimately the contribution of the interface to the macroscopic properties.
Journal of the Mechanical Behavior of Biomedical Materials


hydrogels, mechanical characterization, atomic force microscopy


Aziz, A. , Wahlquist, J. , Sollner, A. , Ferguson, V. , DelRio, F. and Bryant, S. (2016), Mechanical characterization of sequentially layered photo-clickable thiol-ene hydrogels, Journal of the Mechanical Behavior of Biomedical Materials, [online], (Accessed April 21, 2024)
Created September 7, 2016, Updated October 12, 2021