Removal of Ampicillin Using Cold Atmospheric-Pressure Plasma Jet and Its Plasma-Activated Water

Abstract

Ampicillin (AMP) is one broad-spectrum β-lactam antibiotics applied widely in the world, and its abuse may cause microbial resistance and pose a threat to human health. Currently, there is still a lack of effective methods for treating various antibiotics in the environment. In the present work, we employed cold atmospheric-pressure plasma (CAP) to treat ampicillin and explored the optimal conditions for the removal of AMP in water, and we made use of CAP jets (CAPJ) with different working gases and also took advantage of the associated plasma-activated water (PAW) to improve the treatment efficiency. Our results showed that air-CAPJ combined with its PAW treatment could best enhance the efficiency of the removal of ampicillin in water. For the mechanism of the AMP degradation by CAPJ and PAW treatment, hydroxyl radical (·OH) was the key factor in the direct plasma processing, while singlet oxygen (<sup>1</sup>O<sub>2</sub>) played the critical role in the indirect PAW treatment. The toxicological assessment confirmed the bio-safety of the CAPJ treatments. Therefore, this work demonstrates an effective method for removing antibiotics such as ampicillin in the environment.