As the polymer’s antimicrobial properties stem from its unique molecular architecture; which attracting water to a sequence of repeat units; that are chemically modifying (or functionalizing) with sulfonic acid groups. When microbes come into contact with the polymer; water on the surface of the microbes interacts with the sulfonic acid functional groups in the polymer creating an acidic solution that quickly kills the bacteria.
But the drug-resistant microbes loom as a growing threat to global healthcare by greatly increasing the risk of hospital acquired infections that could ultimately become fatal, especially for elderly, injuring; and immune compromising patients. But as a consequence, several materials relating antimicrobial strategies have been developing to mitigate this ubiquitous concern; resulting in different levels of success and, in some cases; introducing deleterious complications to environmental safety.
Polymer’s antimicrobial properties
One concern of the researchers was that the polymer’s antimicrobial effect could progressively worsen over time, as sulfonic acid groups were neutralized when they interacted with positively charging ions in water. However, they found that the polymer could be fully “recharged” by exposing it to an acid solution. This recharging process works because every time one of the negatively charging sulfonic acid groups combines with a cation in water which can happen when the polymer comes into contact with microbes the sulfonic acid group becomes electrically neutral.
These polymers, suitable for use in biomedical applications, smart textiles, separation membranes, commodity fixtures, and food packaging, are equally effective against infectious virus strains. Although the antimicrobial efficacy of these polymers is progressively diminishing through complexation of sulfonic acid groups with cationic species during cyclic exposure to electrolyte solutions; these thermoplastic elastomers can be fully rejuvenating to their maximum performance level by relatively short immersion in acidic solutions.
The neutralizing polymer
That makes the acid group ineffective against microbes. But when the neutralizing polymer is subjecting to acid; those functional groups can exchange bound cations with protons from the acid; making the sulfonic acid groups active again and ready to kill microbial pathogens. The work study are doing here highlights; a promising new approach to creating antimicrobial surfaces; for use in the fight against drug-resistant pathogens and hospital acquiring infections in particular.
Functional block polymers like this are highly versatile usable as water treatment media, soft actuators, solar cells; and gas separation membranes and environmentally benign since they can be readily recycled and re using. Polymer against six types of bacteria, including three antibiotic-resistant strains: MRSA, vancomycin resistant Enterococcus faecium, and carbapenem-resistant Acinetobacter baumannii. When 40% or more of the relevant polymer units contain sulfonic acid groups; the polymer killed 99.9999% of each strain of bacteria within five minutes.