Campus Units

Chemical and Biological Engineering, Materials Science and Engineering, Ames Laboratory

Document Type

Article

Research Focus Area

Health Care Technology and Biomedical Engineering

Publication Version

Published Version

Publication Date

6-27-2018

Journal or Book Title

ACS Omega

Volume

3

Issue

6

First Page

6998

Last Page

7007

DOI

10.1021/acsomega.8b00683

Abstract

Gellan gum is a naturally occurring polymer that can cross-link in the presence of divalent cations to form biocompatible hydrogels. However, physically cross-linked gellan gum hydrogels lose their stability under physiological conditions, thus restricting the applications of these hydrogels in vivo. To improve the mechanical strength of the gels, we incorporated methacrylate into the gellan gum and chemically cross-linked the hydrogel through three polymerization methods: step growth through thiol–ene photoclick chemistry, chain-growth via photopolymerization, and mixed model in which both mechanisms were employed. Methacrylation was confirmed and quantified by proton nuclear magnetic resonance (1H NMR) and Fourier transform infrared spectroscopy. The mechanical properties and chemistry of the cross-linked gels were systematically altered by varying the reaction conditions. The compression moduli of the resulting hydrogels ranged between 6.4 and 17.2 kPa. The swelling ratios of the hydrogels were correlated with the compression moduli and affected by the addition of calcium. In vitro enzymatic degradation rate was found to depend on the degree of methacrylation. NIH/3T3 fibroblast cell proliferation and morphology were related to substrate stiffness, with a high stiffness leading generally to higher proliferation. The proliferation is further affected by the thiol–ene ratio. These results suggest that a hydrogel platform based on the gellan gum can offer versatile chemical modifications and tunable mechanical properties. The influence of these substrates on cell behavior suggests that the gellan gum hydrogels have the flexibility to be engineered for a variety of biomaterials applications.

Comments

This article is published as Xu, Zihao, Zhuqing Li, Shan Jiang, and Kaitlin M. Bratlie. "Chemically Modified Gellan Gum Hydrogels with Tunable Properties for Use as Tissue Engineering Scaffolds." ACS Omega 3, no. 6 (2018): 6998-7007. doi: 10.1021/acsomega.8b00683. Posted with permission.

Rights

This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes.

Copyright Owner

American Chemical Society

Language

en

File Format

application/pdf

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