10th International Aerosol Conference September 2 - September 7, 2018 America's Center Convention Complex St. Louis, Missouri, USA
Abstract View
Measuring Changes in Bioaerosol Fluorescence over Time with the WIBS
ELIZABETH CORSON, Jonathan Eshbaugh, JHU/APL
Abstract Number: 858 Working Group: Bioaerosols
Abstract Exposure of biological aerosols to atmospheric processing may result in changes in viability and spectral signatures. Many instruments rely on particle fluorescence measurements to detect biological aerosols. Therefore, understanding changes in fluorescence signature over time is critical for accurate bioaerosol detection. The Wideband Integrated Bioaerosol Sensor (WIBS-4A, Droplet Measurement Technologies Inc.) measures particle fluorescence at two excitation wavelengths, 280 nm and 370 nm, and two emission spectra, 310-400 nm and 420-650 nm. This multichannel approach to fluorescence measurement produces informative data about the state of a bioaerosol population over time. Two bioaerosol aging campaigns were completed using a rotating drum to maintain an aerosol population and expose the aerosol to atmospheric processing effects, such as water vapor, ultraviolet light, and ozone. The aerosol was measured over time using a WIBS-4A and an Ultraviolet Aerodynamic Particle Sizer (UVAPS, TSI Inc.). Changes in fluorescence signatures over time were observed in a vegetative bacteria and a protein, especially when those aerosols were exposed to ozone and water vapor. Fluorescence data will be presented with an emphasis on methodology for investigating bioaerosol fate and how to interpret raw WIBS data in this context.