Continuous Surveillance of Bioaerosols On-Site Using an Automated Bioaerosol-Monitoring System

Abstract

Real-time on-site monitoring of bioaerosols in an air environment is important for preventing various adverse health effects including respiratory diseases and allergies caused by bioaerosols. Here, we report the development of an on-site automated bioaerosol-monitoring system (ABMS) using integrated units including a wet-cyclone bioaerosol sampler, a thermal-lysis unit for extracting adenosine triphosphate (ATP), an ATPdetection unit based on the immobilization of luciferase/luciferin for bioluminescence reactions, and a photomultiplier tube-based detector. The performance of the bioaerosol detection system was verified using Escherichia coli (E. coli) as a model source. Each unit was optimized to process ∼9.6 × 10 5 times the concentrated ratio of collected bioaerosol samples, using a 3 min lysis time to extract ATP, and has a detection limit of ∼375 colony-forming units (CFUs)/mL with more than 30 days of stability for the immobilizedluciferase/luciferin detection unit supported by a glass-fiber conjugation pad. After the integration of all units, the ABMS achieved E. coli bioaerosol monitoring with continuous detection at 5 min intervals and a minimum detection limit of ∼130 CFU/m air 3 . Furthermore, the rapid responsivity and stable operation performance of the ABMS under test-bed conditions and during a field test demonstrated that the ABMS is capable of continuously monitoring bioaerosols in real-time with high sensitivity. The monitoring system developed here with immobilization strategies for bioluminescence reactions triggered by ATP extracted from collected bioaerosol samples using a simple heat-lysis method may help establish sustainable platforms to obtain stable signals for the real-time detection of bioaerosols on-site.

Challenges and Perspectives for Biosensing of Bioaerosol Containing Pathogenic Microorganisms

“…The results showed that this centrifugation method could collect >95% of the particles with a diameter of >0.5 μm and the bioaerosols containing Staphylococcus epidermidis and Micrococcus luteus [ 46 ]. Combined with the adenosine triphosphate-bioluminescence technique, this method was able to detect the bioaerosols containing E.coli cells as low as 130 CFU/m 3 [ 47 ].…”

“…The bioluminescent intensity of the pad was finally measured using the photomultiplier tube. This bioluminescence assay was able to detect the bioaerosols with pathogenic microorganisms as low as ∼130 CFU/m 3 in seconds [ 47 ]. Besides, as shown in Figure 9 B, the bioaerosols containing bacteria were first charged by the negative ions and then collected in a flowing liquid containing cell lysis buffer and ATP bioluminescence reagents.…”

Paper-Based Airborne Bacteria Collection and DNA Extraction Kit

“…Most airborne pathogens are existing types of bio-aerosols [7], and airborne pathogens are generally detected via aerosol collection and analysis of collected microorganisms. Due to occasional extremely low level concentrations and much larger volumes compared to other types of samples, air sampling has been a bottleneck for the diagnosis of airborne pathogens [8,9].…”

“…However, some aerosol collection techniques require heavy instruments, long sampling times, or additional complex settings. The availability of rapid, accurate, and easy-to-use techniques with effective aerosol analysis is still a technical issue [7,20].…”

Atmospheric Biodetection Part I: Study of Airborne Bacterial Concentrations from January 2018 to May 2020 at Saclay, France

“…Recently, in order to investigate the hourly variability of PBAPs, online measurements by fluorescence methods have been developed and used in different environments [ 35 , 36 ]. Additionally, online detection and collection with automated wet cyclones were used to avoid culture and laboratory work for species identification [ 37 ]. To date, these fluorescent methods have limitations and suffer from artifacts without providing a clear characterization of the bioaerosol.…”