Chemometrics-assisted excitation-emission fluorescence spectroscopy on nylon membranes

BORTOLATO, S. A.; ARANCIBIA, J. A.; ESCANDAR, G. M.

ANALYTICAL CHEMISTRY

American Chemical Society

Año: 2008 vol. 80 p. 8276 - 8286

0003-2700

This work presents a novel approach for the simultaneous ultra trace determination of benzo[a]pyrene and dibenzo[a,h]anthracene, the two most carcinogenic polycyclic aromatic hydrocarbons (PAHs), in a very interfering environment, combining the recently discovered ability of the nylon membrane to strongly retain and concentrate PAHs on its surface, the sensitivity of molecular fluorescence and the selectivity of second-order chemometric algorithms. The fluorescence excitation-emission matrices, directly measured on a nylon-membrane surface, are processed by applying parallel factor analysis (PARAFAC) and unfolded partial least-squares coupled to residual bilinearization (U-PLS/RBL). The superiority of U-PLS/RBL to quantify BaP and DBA at concentrations below 10 ng L–1 in the presence of the remaining fourteen US EPA (United States Environmental Protection Agency) PAHs at total concentrations ranging from 1400 and 14000 ng L–1 is demonstrated. The present method successfully faces this complex challenge without using organic solvents, which are to known produce environmental contamination. Finally, the high sensitivity of the present method avoids pre-concentration and elution steps, considerably decreasing the analysis time and the experimental errors. Because the instrumental involved in the determination is non sophisticated, the experiments could be carried out in routine laboratories.