Multifunctional polymeric guanidine and hydantoin halamines with broad biocidal activity

Area of Science:

• Materials Science
• Polymer Chemistry
• Antimicrobial Agents

Background:

• The COVID-19 pandemic highlighted the need for advanced antiviral surface materials.
• Existing biocides face challenges with overuse and potential resistance.
• Novel polymers with enhanced antimicrobial properties are crucial for future pandemic preparedness.

Purpose of the Study:

• To investigate novel polyamines functionalized with biguanide, guanidine, and hydantoin groups for enhanced biocidal activity.
• To develop halogenated N-halamine polymers with potent antiviral, antifungal, and antibacterial properties.
• To assess the biocompatibility and potential application of these polymers as non-leaching coatings.

Main Methods:

• Synthesized and halogenated polyamines including poly(N-vinylguanidine) (PVG), poly(allylamine-co-4-aminopyridine-co-5-(4-hydroxybenzylidene)hydantoin) (PAH), and poly(hexamethylene biguanide) (PHMB).
• Generated N-halamines via in situ hypohalous acid (HOBr or HOCl) treatment.
• Evaluated virucidal activity against HCoV-229E, fungicidal activity against C. albicans, and bactericidal activity against MRSA and VRE.
• Assessed cytotoxicity using HeLa cell monolayers.

Main Results:

• Halogenation significantly enhanced the virucidal activity of all tested polymers against HCoV-229E.
• Brominated PHMB-Br demonstrated high efficacy (>5) at 1 mg/L and complete inhibition at 10 mg/mL.
• Brominated PVG-Br and PAH-Br exhibited fungicidal activity, while PHMB was fungistatic.
• All tested polymers showed excellent bactericidal activity against resistant strains (MRSA, VRE).
• Brominated polymers were non-toxic to HeLa cells, indicating good biocompatibility.

Conclusions:

• Halogenated N-halamine polymers derived from polyamines exhibit potent and broad-spectrum antimicrobial activity.
• These polymers are effective against viruses, fungi, and bacteria, including drug-resistant strains.
• The developed N-halamine polymers are biocompatible and suitable for creating non-leaching antimicrobial coatings.
• These materials represent a valuable addition to the arsenal of biocides for pandemic prevention and control.