Quantitative Comparison of the Autofluorescence of Bacteria and Polystyrene Microspheres under Violet Wavelength Excitation for Verification of Fluorescence-based Bioaerosol Detector Results

Abstract

The autofluorescence intensity of bacteria and fungal spores was quantified by fluorescence microscopy in order to obtain the information for evaluating fluorescence-based bioaerosol detectors and was comparable to that of some types of polystyrene microspheres PSMs . Although the intensity for microbes was distributed across a wide range over an order of magnitude in gray scale, it was in the intensity range of certain PSMs. Furthermore, some of those bacteria and PSMs were aerosolized in a test chamber and the fluorescence intensity was measured with a bioaerosol detector. Although there was a slight difference in the order of intensity from the results obtained by fluorescence microscopy, the fluorescence-based bioaerosol detector showed the intensity was in a comparable range.

Microscopy for Detection of Extant Life

“…These signals are weak and nonspecific (Fig. 1C) and rarely used for bacterial detection; other molecules such as flavins show stronger signals and are attracting attention among microbiologists 20,21 .…”

Interactive comment on amt-2017-407 by Könemann et al.

“…Fluorescent polystyrene latex spheres (PSLs) play a particularly important role in the characterization and calibration of instruments that rely on particle autofluorescence (also called intrinsic fluorescence) detection. For example, PSLs are commonly used for testing and calibration of instruments such as flow cytometers and lightinduced fluorescent (LIF) instruments (e.g., Hasegawa, 2013;Healy et al, 2012;Jung et al, 2012;Kanaani et al, 2008;Robinson et al, 2017;Toprak and Schnaiter, 2013).…”

Technical note: Characterization of steady-state fluorescence properties of polystyrene latex spheres using off- and on-line spectroscopic methods

“…For example, PSLs are commonly used for testing and calibration of instruments such as flow cytometers and laser/light-induced fluorescent (LIF) instruments (e.g. Hasegawa, 2013;Healy et al, 2012;Jung et al, 2012;Kanaani et al, 2008;Robinson et al, 2017;Toprak & Schnaiter, 2013). 10 LIF techniques can be utilized for rapid characterization of bioaerosols, also referred to as primary biological aerosol particles (PBAP).…”