Application of a pm-rf-APGD-type plasma brush for deactivation of antibiotics from liquid solutions leads to impaired development of drug resistance by bacterial pathogens

Abstract

The presence of antibiotics residuals in the natural environment contributes to development and spread of drug resistance determinants among bacteria, often including clinically significant human pathogens. To tackle with this threat, we constructed a plasma brush, generating pulse-modulated radio-frequency atmospheric pressure glow discharge (pm-rf-APGD), named pm-rf-APGD-type plasma brush, intended for degradation of biologically active pharmaceuticals from both single- and five-component solutions of ciprofloxacin (CFX), enrofloxacin (EFX), ofloxacin (OFX), doxycycline (DXC), and trimethoprim (TMP). The mean antibiotics removal efficiency, achieved mainly due to the action of reactive oxygen species (ROS), was 93.3 %. This removal efficiency corresponded to a mean 62.7% decrease in the antibacterial activities. We revealed the transformation products resulting from an oxygen attack and/or internal fragmentation of the treated pharmaceuticals. Based on a laboratory evolution study, bacterial exposure to the pm-rf-APGD-treated drug lead to significantly lower rates of antibiotic resistance development in juxtaposition with a long-term exposure to the sublethal dose of the active molecules. Thus, we anticipate a great potential of high-throughput, continuous flow, eco-friendly pm-rf-APGD-type plasma brush for routine decontamination processes in the future disposal pipelines of pharmaceuticals-containing wastewaters.