Swelling and mechanical behaviors of chemically cross-linked hydrogels of elastin-like polypeptides.

Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, U.S. Gov't, P.H.S.

Genetically engineered elastin-like polypeptides consisting of Val-Pro-Gly-X-Gly repeats, where X was chosen to be Lys every 7 or 17 pentapeptides (otherwise X was Val), were synthesized and expressed in E. coli, purified, and chemically cross-linked using tris-succinimidyl aminotriacetate to produce hydrogels. Swelling experiments indicate hydrogel mass decreases by 80-90% gradually over an approximate 50 degrees C temperature range. Gels ranged in stiffness from 0.24 to 3.7 kPa at 7 degrees C and from 1.6 to 15 kPa at 37 degrees C depending on protein concentration, lysine content, and molecular weight. Changes in gel stiffness and loss angle with cross-linking formulation suggest a low-temperature gel structure that is nearly completely elastic, where force is transmitted almost exclusively through fully extended polypeptide chains and chemical cross-links, and a high-temperature gel structure, where ELP chains are contracted and force is transmitted through chemical cross-links as well as frictional contact between polypeptide chains.

Full Text

Duke Authors

Cited Authors

  • Trabbic-Carlson, K; Setton, LA; Chilkoti, A

Published Date

  • May 2003

Published In

Volume / Issue

  • 4 / 3

Start / End Page

  • 572 - 580

PubMed ID

  • 12741772

International Standard Serial Number (ISSN)

  • 1525-7797

Digital Object Identifier (DOI)

  • 10.1021/bm025671z

Language

  • eng

Citation Source

  • PubMed