Direct mass-quantification of particulate deposits of polycyclic aromatic hydrocarbons by Fourier transform imaging microscopy

Successful coupling of imaging microscopy with Fourier transform spectromet ry provides a new methodological approach. This was applied to the direct a nalysis of particulate deposits of polycyclic aromatic hydrocarbons (PAHs). The fluorescence signals of single microscopic particulates were found to be proportional to their mass, obtained from the corresponding HPLC results . Special fluorescence characteristics related to individual particle analy sis were studied. The sensitivity of the proposed method to PAHs in soil is in the sub-ppb range, similar to HPLC results. Analysis of inhomogeneous P AH-particulates was demonstrated, as well as the resolution of photochemica l products of PAHs. The effects of particulate orientation relative to the detector upon quantification are discussed.