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Updated: Aug 7, 2026
10:14
Expression and Purification of Nuclease-Free Oxygen Scavenger Protocatechuate 3,4-Dioxygenase
Published on: November 8, 2019
Oxygen Initiated Crosslinking of Electronically Optimized Catechols
Animesh Ghosh1, Vicki X Wu1, Konrad Kozlowski1
1School of Materials Science and Engineering (MSE), Division of Materials Technology, Nanyang Technological University (NTU), Singapore, Singapore.
Macromolecular Rapid Communications
|August 6, 2026
Summary
This study introduces a novel one-component bioadhesive using catechol-grafted polymers. The new design activates upon oxygen exposure, overcoming limitations of previous non-toxic tissue adhesives.
Area of Science:
- Biomaterials Science
- Polymer Chemistry
- Adhesive Technology
Background:
- Catechol-grafted macromolecules show promise for non-toxic bioadhesives but face commercialization hurdles.
- Existing limitations include harmful crosslinkers, poor shelf-stability, and complex preparation methods.
- Over-reliance on L-dopamine-based crosslinkers hinders progress in bioadhesive development.
Purpose of the Study:
- To develop novel one-component (1C) bioadhesives by evaluating alternative catechol scaffolds and oxidation processes.
- To design bioadhesives activated by surface contact and oxygen exposure, bypassing traditional limitations.
- To create a stable, easily prepared, and effective non-toxic tissue adhesive.
Main Methods:
- Grafting of branched polyethylenimine (PEI) dendrimers with 5-methoxy-3,4-dihydroxybenzaldehyde (5-OMe-3,4-DBA) via Schiff-base click chemistry.
- Formulation of PEI-(5-OMe-3,4-DBA)20, where 20% of PEI primary amines are functionalized.
- Evaluation of spontaneous quinone conversion using 1H-NMR and UV-vis spectroscopy, and assessment of gelation time and shear strength.
Main Results:
- PEI-(5-OMe-3,4-DBA)20 initiates rapid crosslinking upon exposure to air/O2 but remains stable anaerobically.
- Structural analysis confirmed spontaneous conversion to quinones, evidenced by 1H-NMR and UV-vis decay kinetics.
- Achieved gelation in under 1 minute with shear strengths of 26 kPa on wetted collagen substrates.
Conclusions:
- Developed a one-component bioadhesive formulation (PEI-(5-OMe-3,4-DBA)20) that overcomes limitations of previous catechol-based adhesives.
- Demonstrated oxygen-activated crosslinking and anaerobic stability, offering a simplified and potentially more stable bioadhesive system.
- The new bioadhesive exhibits rapid gelation and significant shear strength, indicating potential for non-toxic tissue adhesion applications.
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