Abstract #0876

In Vivo Tracking of Biomaterial Degradation of Hydrogels Synthesized with Protein Polymer-Based Contrast Agents

Emily Alexandria Waters¹, Lindsay Karfeld-Sulzer², Ellen Kohlmeir³, Hermann Kissler⁴, Xiaomin Zhang⁴, Dixon Kaufman⁴, Annelise Barron^1,2, Thomas Meade^1,3

¹Chemistry, Northwestern University, Evanston, IL, USA; ²Chemical and Biological Engineering, Northwestern University, Evanston, IL, USA; ³Biochemistry, Molecular and Cell Biology, Northwestern University, Evanston, IL, USA; ⁴Transplant Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, USA

Biomaterial scaffolds are employed for controlled-release drug delivery and as extracellular matrices to support cellular therapies, but are difficult to track over time. Biomaterial scaffolds with covalently incorporated T1-shortening agents could improve contrast with surrounding tissues. We have developed artificial protein polymers generated by recombinant protein expression in E. Coli. These proteins have evenly spaced lysine residues which can be modified with Gd(III) chelators and enzymatically cross-linked into hydrogels. The relaxivity can be tuned by varying the lysine spacing and number of repeats in the polymer. We demonstrate in vivo MRI tracking of degradation of a hydrogel containing these polymers.