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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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This content will become publicly available on August 1, 2026
Chlorocatechol-functionalized gelatin nanoparticles as a hemostatic agent with antimicrobial properties
Hemorrhage is one of the leading preventable causes of death associated with trauma, which is often complicated by wound infection. Current hemostatic materials are not ideal and lack antimicrobial properties needed for infection prevention. Here, we tested the feasibility for 6-chlorodopamine-functionalized gelatin (GDC) nanoparticles to function as a hemostatic powder with strong tissue adhesion and antibacterial properties. 6-Chlorodopamine contains a catechol sidechain that is further modified with an electron withdrawing chlorine atom, and provides strong tissue adhesion and antimicrobial property. These gelatin nanoparticles are not covalently crosslinked, which enablde them to rapidly transition into an adhesive film when hydrated with an aqueous solution or blood. The chlorination of catechol significantly increased structural integrity, interfacial bonding to tissue surface, and the rate of film formation. Additionally, GDC nanoparticles are noncytotoxic and nonhemolytic, and effectively killed Gram-positive (Staphylococcus epidermidis, Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. Finally, GDC nanoparticles achieved significantly faster hemostasis and reduced blood loss when compared to a commercial fibrin glue, Tisseel, in tail transection and liver hemorrhage models performed in mice. These findings highlight the potential of GDC nanoparticle as a versatile, multifunctional hemostatic agent capable of both rapid hemorrhage control and infection prevention.
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- PAR ID:
- 10633318
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Acta Biomaterialia
- ISSN:
- 1742-7061
- Subject(s) / Keyword(s):
- Chlorocatechol Hemostatic nanoparticles Antibacterial Bioadhesive
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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