Silk Hydrogels of Tunable Structure and Viscoelastic Properties Using Different Chronological Orders of Genipin and Physical Cross-Linking.

Autor: Elliott WH; †Department of Industrial Engineering and BIOtech Research Centre, University of Trento, Via Sommarive 9, 38123 Trento, Italy.; ‡Department of Mechanical Engineering, University of Colorado, 1111 Engineering Drive, 427 UCB, Boulder, Colorado 80309, United States., Bonani W; †Department of Industrial Engineering and BIOtech Research Centre, University of Trento, Via Sommarive 9, 38123 Trento, Italy.; §European Institute of Excellence on Tissue Engineering and Regenerative Medicine, and INSTM Trento Research Unit, 38123 Trento, Italy., Maniglio D; †Department of Industrial Engineering and BIOtech Research Centre, University of Trento, Via Sommarive 9, 38123 Trento, Italy.; §European Institute of Excellence on Tissue Engineering and Regenerative Medicine, and INSTM Trento Research Unit, 38123 Trento, Italy., Motta A; †Department of Industrial Engineering and BIOtech Research Centre, University of Trento, Via Sommarive 9, 38123 Trento, Italy.; §European Institute of Excellence on Tissue Engineering and Regenerative Medicine, and INSTM Trento Research Unit, 38123 Trento, Italy., Tan W; ‡Department of Mechanical Engineering, University of Colorado, 1111 Engineering Drive, 427 UCB, Boulder, Colorado 80309, United States., Migliaresi C; †Department of Industrial Engineering and BIOtech Research Centre, University of Trento, Via Sommarive 9, 38123 Trento, Italy.; §European Institute of Excellence on Tissue Engineering and Regenerative Medicine, and INSTM Trento Research Unit, 38123 Trento, Italy.
Jazyk: angličtina
Zdroj: ACS applied materials & interfaces [ACS Appl Mater Interfaces] 2015 Jun 10; Vol. 7 (22), pp. 12099-108. Date of Electronic Publication: 2015 May 27.
DOI: 10.1021/acsami.5b02308
Abstrakt: Catering the hydrogel manufacturing process toward defined viscoelastic properties for intended biomedical use is important to hydrogel scaffolding function and cell differentiation. Silk fibroin hydrogels may undergo "physical" cross-linking through β-sheet crystallization during high pressure carbon dioxide treatment, or covalent "chemical" cross-linking by genipin. We demonstrate here that time-dependent mechanical properties are tunable in silk fibroin hydrogels by altering the chronological order of genipin cross-linking with β-sheet formation. Genipin cross-linking before β-sheet formation affects gelation mechanics through increased molecular weight, affecting gel morphology, and decreasing stiffness response. Alternately, genipin cross-linking after gelation anchored amorphous regions of the protein chain, and increasing stiffness. These differences are highlighted and validated through large amplitude oscillatory strain near physiologic levels, after incorporation of material characterization at molecular and micron length scales.
Databáze: MEDLINE