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Abstract Catechol is an oft‐used crosslinking precursor and adhesive molecule for designing in situ curable biomaterials and adhesives and the addition of chemical or enzymatic oxidants is required to initiate fast curing. Here, the feasibility for 6‐hydroxydopamine (6‐OHDA)‐modified 8‐armed polyethylene glycol (PEG) (8‐arm PEG‐DA‐OH) to cure through autoxidation is evaluated. The modification of catechol side chain with an electron‐donating hydroxyl group at the six‐position drastically increased the rate of oxidation and the adhesive cured in just over 1 min through autoxidation. The cure time is decreased to under 40 s with the addition of branched polyethyleneimine (PEI). UV–vis spectra revealed that the deprotonated quinone of 6‐OHDA is a key oxidation intermediate for chemical crosslinking between 6‐OHDA and with primary amine. PEG functionalized with unmodified catechol do not solidify through autoxidation, which highlights the contribution of the electron‐donating hydroxyl group in promoting fast oxidation and crosslinking. Eight‐arm PEG‐DA‐OH and PEI mixture also demonstrated significantly higher adhesion strength to pericardium tissues when compared to a commercial PEG‐based adhesive, DuraSeal. This report highlights 6‐OHDA as an effective crosslinking precursor and adhesive molecule for designing injectable adhesives that do not require externally added oxidants and the adhesive is activated by simple dissolution in an aqueous solution.
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This content will become publicly available on December 12, 2025
Modular synthesis and facile network formation of catechol functionalized triblock copolymers
We report the synthesis of catechol-functionalized symmetric triblock polymers comprising densely functionalized catechol endblocks using anionic ring-opening polymerization (AROP) and thiol–ene click chemistry.
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- Award ID(s):
- 2048285
- PAR ID:
- 10569811
- Publisher / Repository:
- RSC
- Date Published:
- Journal Name:
- Chemical Communications
- Volume:
- 60
- Issue:
- 100
- ISSN:
- 1359-7345
- Page Range / eLocation ID:
- 14952 to 14955
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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