Recent advances in four- and five-way excitation-emission luminescence-based data acquisition and modeling for analytical applications

MUÑOZ DE LA PEÑA, ARSENIO; ALCARAZ, MIRTA RAQUEL; MONAGO-MARAÑA, OLGA ; GOICOECHEA, HÉCTOR CASIMIRO

Menorca

Encuentro; X Colloquium Chemiometricum Mediterraneum; 2019

The growing interest in multi-way analysis is reflected in the large number of reports that are found in the literature. Numerous analytical applications based on multivariate calibration have been developed capitalizing on the advantages offered by the higher-order modeling. Nonetheless, third- and fourth-order analytical applications are still scarce despite all the benefits that have been demonstrated for third- and fourth-order calibration analysis [1]. This work shows a report focused on excitation ? emission (fluorescence and phosphorescence) matrices generation, employing different variables as the third data mode (time retention in chromatography, pH gradient, fluorescence/phosphorescence lifetime, kinetics, or other chemical treatments). The synergistic effect of combining excitation-emission luminescence data with higher-order calibration has been widely exploited in different fields (environmental, biological, foods). Fully capitalizing on the second-order advantage, it had been possible to develop appealing analytical applications in spite of the data complexity. The experimental works reported up to date will be presented and discussed in order to illustrate concepts. As an example, Figure 1 shows original fluorescence images, acquired with a CCD-based fluorescence detector, in function of the chromatographic retention time, and subjected to four-way PARAFAC decomposition [2]. The existence of third-order advantages, whose has been supported with experimental evidences by a number of authors, will be reviewed. The main advantages that have been supported with experimental evidences are 1) the possibility of decomposing a data array for each sample and independent of other samples, 2) the enhancement of the sensitivity and selectivity, by incorporation of additional information of the sample through a third instrumental mode and 3) the possibility to tackle collinearity problems arisen from the introduction of an extra mode. However, more works on the development on the fundamental theories and new applications are needed to fully understand the properties of third? and fourth- order calibration.