Oxime cross-linked alginate hydrogels with tunable stress relaxation.

Oxime cross-linked alginate hydrogels with tunable stress relaxation. Biomacromolecules. 2019 Oct 22;: Authors: Sanchez-Moran H, Ahmadi A, Vogler B, Roh KH Abstract Stress relaxation is an important design parameter of biomaterials that can provide an artificial microenvironment mimicking natural extracellular matrices (ECMs). Here, we report a novel hydrogel platform based on sodium alginate (NaAlg) with tunable stress relaxation. We first developed a new synthetic route to introduce alkoxyamine functional groups into the alginate polymer backbone. By mixing the resulting polymer (NaAlg-AA) with aldehyde-containing oxidized alginate (NaAlg-Ald), oxime cross-linked alginate hydrogels were prepared. We demonstrate that highly tunable stress relaxation as well as mechanical properties can be achieved by systematically varying the composition (concentration, polymer mixing ratios, degree of oxidation of NaAlg-Ald) or environmental factors (pH, temperature, and use of catalyst). Combined with the natural capability of the alginate to be cross-linked by divalent cations, the developed hydrogel formations possess a unique capability of dual cross-linking mechanisms with different gelation kinetics. We demonstrated that this dual cross-linking capability can i) be utilized for creation of hydrogels in micro-bead or micro-thread geometries and ii) be useful for biomedical applications that require both fast encapsulation of cells in hydrogel...
Source: Biomacromolecules - Category: Biochemistry Authors: Tags: Biomacromolecules Source Type: research