Microscopic Chemical Imaging for Analysis of Polycyclic Aromatic Hydrocarbons in Aerosols

Abstract

A chemical imaging method has been developed and applied for analysis of polycyclic aromatic hydrocarbons (PAH) in aerosols. It is based on fast collection of aerosol particles on non-fluorescing filters, followed by microscopic imaging of the induced fluorescence due to aerosol contamination. The proposed imaging technique provides full fluorescence spectrum at each pixel of the inspected object. It is based on imaging the interferograms produced by a Sagnac interferometer onto a cooled CCD camera in such a way that Fourier transform can be performed later at each pixel of the image. Application of classification algorithms enables simultaneous analysis of several PAH contaminants on the filter. Detection limits are as low as 10 fg.