AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
A New Portable High-flow Aerosol-to-Hydrosol Sampler for Rapid Microbial Detection
XINYUE LI, Maosheng Yao, Peking University
Abstract Number: 807 Working Group: Bioaerosols
Abstract Bioaerosol has considerable impact in public health safety, ambient air quality and atmospheric chemical processes with its unique biological components and biological activities. The methods of rapid bioaerosol collection and detection is widely required in many sectors. Traditional bioaerosol samplers always have low sampling flow and not portable. It is difficult to recognize the key microbial species and its concentration timely for various microbial exposure scenarios that require rapid response. So our lab group has developed a new portable high-flow Aerosol-to-Hydrosol sampling technology. The sampling flow rate is up to 400 L/min, just weighs about 3.4 kg. Airborne biological particles in the air are separated by the principle of cyclonic inertia and trapped in a disinfected cube with 2 ml DI-water. The sampler has been tested with Aerosolized Pseudomonas fluorescens (Gram-negative bacteria), Bacillus subtilis (Gram-positive bacteria), and Polystyrene (PS) uniform microspheres under laboratory controlled conditions. The microspheres were sampled to determine their physical collection efficiency, besides indoor and outdoor ambient air have also been sampled for culturing and quantitative polymerase chain reaction (qPCR) to evaluate the microbial collection in the actual environment. The sampler was found to have a cut-off sizes of about 0.58 μm, the physical collection efficiencies for Bacillus subtilis (0.86 μm) and Pseudomonas fluorescens (0.61 μm) were 86.7% and 74.2%, respectively. The result of culture counting and qPCR test found that the sampler can collect high concentration and biologically active bioaerosol samples in 2 minutes. However, as the sampling time increases, the evaporation loss of the sample liquid and the increase of the concentration of particulate matter in the sample liquid increase the loss of particulate matter, and the sampling efficiency decreases. Compared with the same type of bioaerosol sampler flow, collection efficiency and portability have been significantly improved.