A polypeptide-based hydrogel system, when prepared from a diblock polymer with a ternary copolypeptide as one block, exhibited thermo-, mechano- and enzyme-responsive properties, which enabled the encapsulation of naproxen (Npx) during the sol–gel transition and its release in the gel state. Statistical terpolymerizations of l -alanine (Ala), glycine (Gly) and l -isoleucine (Ile) NCAs at a 1 : 1 : 1 feed ratio initiated by monomethoxy monoamino-terminated poly(ethylene glycol) afforded a series of methoxy poly(ethylene glycol)- block -poly( l -alanine- co -glycine- co - l -isoleucine) (mPEG- b -P(A-G-I)) block polymers. β-Sheets were the dominant secondary structures within the polypeptide segments, which facilitated a heat-induced sol-to-gel transition, resulting from the supramolecular assembly of β-sheets into nanofibrils. Deconstruction of the three-dimensional networks by mechanical force (sonication) triggered the reverse gel-to-sol transition. Certain enzymes could accelerate the breakdown of the hydrogel, as determined by in vitro gel weight loss profiles. The hydrogels were able to encapsulate and release Npx over 6 days, demonstrating the potential application of these polypeptide hydrogels as an injectable local delivery system for small molecule drugs.
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In situ crosslinking temperature‐responsive hydrogels with improved delivery, swelling, and elasticity for endovascular embolization
Endovascular embolization of cerebral aneurysms is a common approach for reducing the risk of often‐fatal hemorrhage. However, currently available materials used to occlude these aneurysms provide incomplete filling (coils) or require a complicated, time‐consuming delivery procedure (solvent‐exchange precipitating polymers). The objective of this work was to develop an easily deliverable in situ forming hydrogel that can occlude the entire volume of an aneurysm. The hydrogel is formed by mixing a solution of a temperature‐responsive polymer containing pendent thiol groups (poly(NIPAAm‐
- NSF-PAR ID:
- 10446080
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Biomedical Materials Research Part B: Applied Biomaterials
- Volume:
- 110
- Issue:
- 8
- ISSN:
- 1552-4973
- Page Range / eLocation ID:
- p. 1911-1921
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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