title: Rapid inactivation of biological species in the air using atmospheric pressure nonthermal plasma.
abstract: Here, nonthermal plasma generated by a dielectric barrier discharge (DBD) system was applied to inactivating aerosolized Bacillus subtilis cells and Pseudomonas fluorescens as well as indoor and outdoor bioaerosols. The culturability, viability, and diversity losses of the microorganisms in air samples treated by the plasma for 0.06-0.12 s were studied using culturing, DNA stain as well as polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) methods. In addition, the viable fraction of bacterial aerosols with and without the plasma treatment was also quantified using qPCR coupled with ethidium monoazide (EMA). It was shown that less than 2% of B. subtilis aerosols survived the plasma treatment of 0.12 s, while none of the P. fluorescens aerosols survived. Viability tests, EMA-qPCR results, and Scanning Electron Microscopy (SEM) images demonstrated that both bacterial species suffered significant viability loss, membrane, and DNA damages. Exposure of environmental bacterial and fungal aerosols to the plasma for 0.06 s also resulted in their significant inactivations, more than 95% for bacteria and 85-98% for fungal species. PCR-DGGE analysis showed that plasma exposure of 0.06 s resulted in culturable bacterial aerosol diversity loss for both environments, especially pronounced for indoor environment. The results here demonstrate that nonthermal plasma exposure could offer a highly efficient air decontamination technology.
authors.affiliation: Department of Biomedical Engineering, College of Engineering, Peking University, Beijing 100871, China.
authors.forename: Yongdong
authors.initials: Y
authors.lastname: Liang
authors.forename: Yan
authors.initials: Y
authors.lastname: Wu
authors.forename: Ke
authors.initials: K
authors.lastname: Sun
authors.forename: Qi
authors.initials: Q
authors.lastname: Chen
authors.forename: Fangxia
authors.initials: F
authors.lastname: Shen
authors.forename: Jue
authors.initials: J
authors.lastname: Zhang
authors.forename: Maosheng
authors.initials: M
authors.lastname: Yao
authors.forename: Tong
authors.initials: T
authors.lastname: Zhu
authors.forename: Jing
authors.initials: J
authors.lastname: Fang
mesh_terms: D000336:Aerosols; D000393:Air Pollutants / Q000302:isolation & purification; D001274:Atmospheric Pressure; D001412:Bacillus subtilis / Q000235:genetics / Q000302:isolation & purification / Q000648:ultrastructure; D058491:Bacterial Load; D004269:DNA, Bacterial / Q000235:genetics; D058645:Denaturing Gradient Gel Electrophoresis; D004203:Disinfection / Q000379:methods*; D008855:Microscopy, Electron, Scanning; D016133:Polymerase Chain Reaction; D011551:Pseudomonas fluorescens / Q000235:genetics / Q000302:isolation & purification
chemical_list: D000336:Aerosols; D000393:Air Pollutants; D004269:DNA, Bacterial