Influence of Sulfur‐Containing Diamino Acid Structure on Covalently Crosslinked Copolypeptide Hydrogels

Abstract

Biologically occurring non‐canonical di‐α‐amino acids were converted into new di‐N‐carboxyanhydride (di‐NCA) monomers in reasonable yields with high purity. Five different di‐NCAs were separately copolymerized with tert‐butyl‐l‐glutamate NCA to obtain covalently crosslinked copolypeptides capable of forming hydrogels with varying crosslinker density. Comparison of hydrogel properties with residue structure revealed that different di‐α‐amino acids were not equivalent in crosslink formation. Notably, l‐cystine was found to produce significantly weaker hydrogels compared to l‐homocystine, l‐cystathionine, and l‐lanthionine, suggesting that l‐cystine may be a sub‐optimal choice of di‐α‐amino acid for preparation of copolypeptide networks. The di‐α‐amino acid crosslinkers also provided different chemical stability, where disulfide crosslinks were readily degraded by reduction, and thioether crosslinks were stable against reduction. This difference in response may provide a means to fine tune the reduction sensitivity of polypeptide biomaterial networks.

Document Details

Document Type
Pub Defense Publication
Publication Date
Sep 17, 2018
Source ID
10.1002/asia.201801031

Entities

People

  • Eric D. Raftery
  • Eric G. Gharkhanian
  • Jack J. McNamara
  • Nicole G. Ricapito
  • Timothy J. Deming

Organizations

  • Defense Advanced Research Projects Agency
  • University of California, Los Angeles

Tags

Fields of Study

  • Chemistry

Readers

  • Nanocomposite Materials Science
  • Organic Chemistry
  • Polymer Science and Technology