Determination of mycotoxins (aflatoxins and ochratoxin A) using fluorescence emission-excitation matrices and multivariate calibration

Mycotoxins (aflatoxins and ochratoxin A) - fungal secondary metabolites - are responsible of producing several harmful effects for both, human and animal health. The aim of this work was to quantify them in cereal samples, using fluorescence emission-excitation matrices (EEM) and second order chemometric methods for the processing and interpretation of the results. Parallel factor analysis (PARAFAC) and Multi-way partial least squares residual bilinearization (Multi-way PLS_RBL or N-PLS_RBL) methods were used. However, the results obtained by the last method were not satisfactory. On the other hand, excellent prediction results were obtained when PARAFAC was applied, with recoveries between 95% and 106% for both analytes and acceptable figures of merit were reached. In order to verify the accuracy of the developed method, real samples were predicted using PARAFAC and enzyme-linked immunosorbent assay (ELISA) - considered as a reference method - and the results gathered by both methods were statistically comparable.