title: Detection of airborne bacteria with disposable bio-precipitator and NanoGene assay.
abstract: We demonstrated the detection of airborne bacteria by a disposable bio-precipitator and NanoGene assay combination. The bio-precipitator employed micro corona discharge at 1960V and at less than 35µA to simultaneously charge, capture and lyse the airborne bacteria. This was enabled by the use of a 15μL liquid anode. Using a custom exposure setup, the target bacterium Bacillus subtilis in the atomization solution was rendered airborne. After exposure, the liquid anode in the bio-precipitator was subsequently measured for DNA concentration and analyzed with the NanoGene assay. As the bacterial concentration increased from 0.0104 to 42.6 g-DCW/L the released DNA concentration in the liquid anode increased from 2.10±1.57 to 75.00±7.15ng/μL. More importantly, the NanoGene assay showed an increase in normalized fluorescence (gene quantification) from 18.03±1.18 to 49.71±1.82 as the bacterial concentrations increased from 0.0104 to 42.6 g-DCW/L. the electrical power consumption of the bio-precipitator was shown to be amenable for portable use. In addition, the detection limit of bio-precipitator and NanoGene assay combination in the context of environmentally relevant levels of airborne bacteria was also discussed.
authors.affiliation: Department of Environmental Science and Engineering, Ewha Womans University, Seoul, Republic of Korea.
authors.forename: Eun-Hee
authors.initials: EH
authors.lastname: Lee
authors.affiliation: School of Electrical Engineering, Korea University, Seoul, Republic of Korea. Electronic address: chuabeelee@gmail.com.
authors.forename: Beelee
authors.initials: B
authors.lastname: Chua
authors.affiliation: Department of Environmental Science and Engineering, Ewha Womans University, Seoul, Republic of Korea. Electronic address: ahjeong.son@gmail.com.
authors.forename: Ahjeong
authors.initials: A
authors.lastname: Son
mesh_terms: D000391:Air Microbiology; D001412:Bacillus subtilis / Q000235:genetics / Q000302:isolation & purification*; D015374:Biosensing Techniques / Q000295:instrumentation*; D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics; D004560:Electricity; D004566:Electrodes; D004867:Equipment Design; D057230:Limit of Detection
chemical_list: D004269:DNA, Bacterial
keywords: Airborne bacteria; Bacillus subtilis; Bio-precipitator; Micro corona discharge; NanoGene assay