Changes in fluorescence spectra of bioaerosols exposed to ozone in a laboratory reaction chamber to simulate atmospheric aging

Opt Express. 2012 Dec 31;20(28):29867-81. doi: 10.1364/OE.20.029867.

Abstract

A laboratory system for exposing aerosol particles to ozone and rapidly measuring the subsequent changes in their single-particle fluorescence is reported. The system consists of a rotating drum chamber and a single-particle fluorescence spectrometer (SPFS) utilizing excitation at 263 nm. Measurements made with this system show preliminary results on the ultra-violet laser-induced-fluorescence (UV-LIF) spectra of single aerosolized particles of Yersinia rohdei, and of MS2 (bacteriophage) exposed to ozone. When bioparticles are exposed in the chamber the fluorescence emission peak around 330 nm: i) decreases in intensity relative to that of the 400-550 nm band; and ii) shifts slightly toward shorter-wavelengths (consistent with further drying of the particles). In these experiments, changes were observed at exposures below the US Environmental Protection Agency (EPA) limits for ozone.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Aerosols / analysis*
  • Atmosphere / chemistry*
  • Laboratories*
  • Levivirus / chemistry*
  • Ozone / chemistry*
  • Spectrometry, Fluorescence
  • Yersinia / chemistry*

Substances

  • Aerosols
  • Ozone