An excitaction-emision fluorescence optosensor for the simultaneos multivariate determination of six polycyclic aromatic hydrocarbons in the presence of uncalibrated interferences

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

Praga

Simposio; XIV International Symposium on Luminiscence Spectrometry; 2010

International Symposium on Luminescence Spectrometry

Polycyclic aromatic hydrocarbons (PAHs) comprise the largest group of chemical compounds known to be cancer-causing agents. Among the 16 PAHs considered as priority by the United States Environmental Protection Agency (US EPA), benzo[a]pyrene, dibenzo[a,h]anthracene, benz[a]anthracene, benzo[b]fluoranthene, benzo[k] fluoranthene and chrysene are the most toxic ones. In the present work a novel approach for the simultaneous trace determination of these six compounds is developed. The selected PAHs are determined in a very interfering environment, combining the advantage of a spectrofluorimetric optosensor coupled to a flow-injection system and the selectivity of second-order chemometric algorithms. The sensor is based on the simultaneous retention of the six PAHs on a non-selective sensing support (octadecyl silane C18 gel) placed inside a quartz flow-cell. After the arrival of the analytes to the sensing zone, the flow is stopped and the excitationemission fluorescence matrix is read in a fast-scanning spectrofluorimeter. Different second-order calibration algorithms were selected for data processing,namely parallel factor analysis (PARAFAC) and unfolded and multidimensional partial least-squares coupled to residual bilinearization (U- and N PLS/RBL). These algorithms achieve the second-order advantage, and are in principle able to overcome the problem of the presence of unexpected interferences. A comparison of the three algorithms is performed.