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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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Utilizing Rapid Hydrogen Peroxide Generation from 6-Hydroxycatechol to Design Moisture-Activated, Self-Disinfecting Coating
A coating that can be activated by moisture found in respiratory droplets could be a convenient and effective way to control the spread of airborne pathogens and reduce fomite transmission. Here, the ability of a novel 6-hydroxycatechol-containing polymer to function as a self-disinfecting coating on the surface of polypropylene (PP) fabric was explored. Catechol is the main adhesive molecule found in mussel adhesive proteins. Molecular oxygen found in an aqueous solution can oxidize catechol and generate a known disinfectant, hydrogen peroxide (H2O2), as a byproduct. However, given the limited amount of moisture found in respiratory droplets, there is a need to enhance the rate of catechol autoxidation to generate antipathogenic levels of H2O2. 6-Hydroxycatechol contains an electron donating hydroxyl group on the 6-position of the benzene ring, which makes catechol more susceptible to autoxidation. 6-Hydroxycatechol-coated PP generated over 3000 μM of H2O2 within 1 h when hydrated with a small amount of aqueous solution (100 μL of PBS). The generated H2O2 was three orders of magnitude higher when compared to the amount generated by unmodified catechol. 6-Hydroxycatechol-containing coating demonstrated a more effective antimicrobial effect against both Gram-positive (Staphylococcus aureus and Staphylococcus epidermidis) and Gram-negative (Pseudomonas aeruginosa and Escherichia coli) bacteria when compared to unmodified catechol. Similarly, the self-disinfecting coating reduced the infectivity of both bovine viral diarrhea virus and human coronavirus 229E by as much as a 2.5 log reduction value (a 99.7% reduction in viral load). Coatings containing unmodified catechol did not generate sufficient H2O2 to demonstrate significant virucidal effects. 6-Hydroxycatechol-containing coating can potentially function as a self-disinfecting coating that can be activated by the moisture present in respiratory droplets to generate H2O2 for disinfecting a broad range of pathogens.
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- PAR ID:
- 10512625
- Publisher / Repository:
- ACS
- Date Published:
- Journal Name:
- ACS Applied Materials & Interfaces
- Volume:
- 16
- Issue:
- 21
- ISSN:
- 1944-8244
- Page Range / eLocation ID:
- 26998 to 27010
- Subject(s) / Keyword(s):
- Reactive oxygen species 6-Hydroxycatechol Catechol Antiviral Antibacterial Self-disinfecting coating
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acsami.4c00213
