pH-Degradable Polymers as Impermanent Antimicrobial Agents for Environmental Sustainability.

Globally, over 100,000 tons of antibiotics are consumed each year with a significant proportion discharged into the environment. As antibiotic usage continues to rise, there is a pressing need to reduce antibiotic pollution by developing antimicrobials whose activity can be switched off after the material has served its intended purpose. We have reported a series of imidazolium polymers incorporating pH-degradable linkers. The polymers show excellent antimicrobial activity across a range of Gram-positive and Gram-negative bacteria and fungi. The introduction of pH-degradable linkers was demonstrated to facilitate environmental degradation of the polymers to inactive small molecules. Both polymers and their degradation products do not induce bacterial resistance and display moderate biodegradation in surface water.