Multiway analysis through direct excitation-emission matrix imaging

SORBELLO, CECILIA; ETCHENIQUE, ROBERTO; ETCHENIQUE, ROBERTO; MORZÁN, EZEQUIEL; MORZÁN, EZEQUIEL; GOICOECHEA, HÉCTOR C.; ALCARAZ, MIRTA R.; GOICOECHEA, HÉCTOR C.; ALCARAZ, MIRTA R.; SORBELLO, CECILIA

ANALYTICA CHIMICA ACTA

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2018 vol. 1032 p. 32 - 39

0003-2670

In this work, a direct in-flow methodology for the acquisition of excitation-emission fluo-rescence matrices is presented. The system is particularly suited for measurements in the order of tens of milliseconds. A light source operated in continuous mode is dispersed through a grating and focused onto a square-section capillary. Under the spatially resolved excitation, the emission is collected, dispersed through a second grating and further focused onto a CCD array sensor. To allow the wavelengths accuracy, a spectral calibration was performed registering the scattering signal of a dispersive element using interference filters ranging from 340 nm to 740 nm. The theoretical performance of the method was analyzed and second-order data obtained for different analyte mixtures are presented and discussed. PARAFAC was applied to evaluate the trilinearity of the obtained data. Mathematical eval-uation by means of the criterion of similarity corroborates the agreement between experi-mental pure spectra and spectral profiles retrieved from PARAFAC. Moreover, the feasibil-ity of the spectrometer to obtain second-order data for analyses with quantitative aims was demonstrated. Finally, fast data acquisition was proved by monitoring a chromatographic analysis of a dyes mixture for the generation of third-order LC-EEM data. Here, an im-provement in the resolution of the different instrumental modes was demonstrated.