Fluorescence spectra and biological activity of aerosolized bacillus spores and MS2 bacteriophage exposed to ozone at different relative humidities in a rotating drum

Atmospheric chemistry of bioaerosols: heterogeneous and multiphase reactions with atmospheric oxidants and other trace gases

“…Santarpia et al 141 exposed samples of aerosolized Yersinia rohdei and MS2 bacteriophage-in- Escherichia coli lysate to atmospheric concentrations of ozone and found that the fluorescence peak at 330 nm decreased in intensity and became slightly blue shifted. Using a rotating drum chamber, Ratnesar-Shumate and coworkers 142 conducted aging experiments by subjecting bioaerosols, Bacillus thuringiensis Al Hakam (BtAH) spores and MS2 bacteriophages to O 3 and varying RH. The experiments yielded a significant decrease in the fluorescence for both BtAH and MS2 at high ozone concentration and high RH when excited at 263 nm excitation.…”

Bioaerosol property and viability affected by various Environmental factors

“…• The ageing process of the resting bioaerosol particles in the reaction chamber was characterizing by the ultra-violet (UV) laser-induced fluorescence spectra measured every half hour, also bacterial viability and PCR from the beginning and the end collected by the AGI sampler. The fluorescence spectra from single individual bioaerosol particles from the rotating drum at each measuring time points throughout each experiment were measured by the single particle fluorescence spectrometer (SPFS) [13]- [15]. It provided dispersed fluorescence spectra covered 280-560 nm excited by a 263-nm laser pulse and 380-650 nm excited by a 351-nm laser pulse associated with an elastic scattering particle size.…”

“…These changes of bioaerosol particles in the atmosphere could be resulting from oxidization by ozone or OH radicals, hydration or desiccation due to fluctuations in relative humidity (RH), degradation by solar irradiation or light-induced photochemical reactions, agglomeration with other aerosols and interactions with secondary organic aerosols (SOA), free radicals, volatile organic compound (VOC), semi-VOC, or inorganic gas-phase compounds (e.g. NOx and SOx) [5]- [15]. There are some studies about the total fluorescence changes for fungal spores as they exposed to flowing air in cultures of different ages [10]; about the changes of viability and inactivation, absorption and fluorescence for bacteria and aromatic amino acids in bulk samples after exposure to ozone [11]- [12]; and about the change of fluorescence and viability for bioaerosols suspended in air while they interact with ozone in different relative humidities [13]- [15].…”

“…NOx and SOx) [5]- [15]. There are some studies about the total fluorescence changes for fungal spores as they exposed to flowing air in cultures of different ages [10]; about the changes of viability and inactivation, absorption and fluorescence for bacteria and aromatic amino acids in bulk samples after exposure to ozone [11]- [12]; and about the change of fluorescence and viability for bioaerosols suspended in air while they interact with ozone in different relative humidities [13]- [15]. However, there is limited study about the effects of these 'open air factors (OAF)' to bioaerosols suspended in real atmosphere.…”

Topical issue on optical particle characterization and remote sensing of the atmosphere: Part II

“…Aerosols are not static, but undergo chemical transformations as they are exposed to their local conditions. RatnesarShumate et al [19] present a novel technology to quantify the evolution that aerosols undergo under different conditions. Characterizing atmospheric conditions on larger spatial scales was the subject of research by Yin et al [20] who correlated cloudiness parameters with the El Niño/ Southern Oscillation.…”