Feasibility of Multidimensional Fluorescence at Low Temperature in Shpol'skii Matrices Combined with PARAFAC for the Quantitation of Polycyclic Aromatic Hydrocarbons

Abstract

The feasibility of determination of four polycyclic aromatic hydrocarbons (PAHs), using multidimensional fluorescence at low temperature in Shpol´skii matrices, was addressed in this work. Excitation -Emission Matrices (EEMs) at low temperature (77 K) were obtained, using an optimized optic fiber consisted of two delivery and eight collection fibers, with an eightaround-two configuration. That configuration improved the sensitivity by six times compared with conventional six-rounded-one configuration. The second-order EEMs data were collected registering the emission spectra from 350 to 480 nm, each 1 nm, varying the excitation wavelength from 250 to 310 nm, each 5 nm, and processed with parallel factor analysis (PARAFAC) for the quantitation of traces of benzo[a]pyrene, benzo[b]fluoranthene, benzo[a] anthracene and chrysene. The results were validated obtaining recoveries ranging from 80 to 120%. The approach takes advantage of the sharp spectra with vibrational information resulting from homogeneous and inhomogeneous band-broadening reduction and could be useful for the analysis of these compounds in different food samples, where maximum levels of them are stablished in several regulations.