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Title: Self-assembly of stimuli-responsive coiled-coil fibrous hydrogels
Owing to their tunable properties, hydrogels comprised of stimuli-sensitive polymers are one of the most appealing scaffolds with applications in tissue engineering, drug delivery and other biomedical fields. We previously reported a thermoresponsive hydrogel formed using a coiled-coil protein, Q. Here, we expand our studies to identify the gelation of Q protein at distinct pH conditions, creating a protein hydrogel system that is sensitive to temperature and pH. Through secondary structure analysis, transmission electron microscopy, and rheology, we observed that Q self-assembles and forms fiber-based hydrogels exhibiting upper critical solution temperature behavior with increased elastic properties at pH 7.4 and pH 10. At pH 6, however, Q forms polydisperse nanoparticles, which do not further self-assemble and undergo gelation. The high net positive charge of Q at pH 6 creates significant electrostatic repulsion, preventing its gelation. This study will potentially guide the development of novel scaffolds and functional biomaterials that are sensitive towards biologically relevant stimuli.  more » « less
Award ID(s):
1728858
PAR ID:
10295847
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Soft Matter
Volume:
17
Issue:
26
ISSN:
1744-683X
Page Range / eLocation ID:
6470 to 6476
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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