Modeling of Four-Way Chromatographic-Fluorescence Arrays for the Quantitation of Fluoroquinolones in Environmental Samples

ALCARAZ, MIRTA; CULZONI, MARÍA JULIA; GOICOECHEA, HÉCTOR

Philadelphia

Congreso; PITTCON 2013; 2013

ACS Division of Analytical Chemistry

Owing to the prevalent acceptance in the analytical community about the need to study increasingly complex samples by improving analytical methods, an intensive research of new multi-way data generation and its consequent modeling with convenient algorithms have been carried out in last years [1]. In this context, four-order chromatographic data arrays modeled with appropriate algorithms appear as an interesting tool for solving complex analytical tasks. In most of the literature applications, the well known parallel factor analysis (PARAFAC) algorithm has been the choice for processing four-way arrays [2]. Moreover, a methodology based on the use of latent variables was adapted for processing four-way arrays, maintaining the second-order advantage: the multiway variant of PLS (U-PLS) coupled to RTL, which calls for extensive studies [3]. Fluoroquinolones are broad-spectrum antibiotics that play an important role in the treatment of serious bacterial infections, especially hospital-acquired infections and others in which resistance to older antibacterial classes is suspected. Third-order data were generated collecting chromatographic fractions every fifteen seconds for every sample and recording excitation emission matrices, for each fraction. Then, time-excitation-emission hypermatrices were arranged for each sample. Four-way arrays (sample plus standards data) were modeled with PARAFAC and N-PLS/RTL, after a convenient data preprocessing (shift and baseline correction). Validation samples (standard mixture solutions prepared in milli-Q water) and real test samples (tap water and well water) were analyzed. As a conclusion, five fluoroquinolones could be quantitated at pg/L levels with acceptable figures of merit as indicators of accuracy (mean recoveries: 90?110%) and precision (CV%= 4?6%) were obtained. [1] GM Escandar, NM Faber, HC Goicoechea, A Muñoz de la Peña, AC Olivieri, RJ Poppi, Trends Anal. Chem. 26(2007)752 [2] R Bro, Chemom. Intell. Lab. Syst. 38(1997)149 [3] AC Olivieri, JA Arancibia, A Muñoz de la Peña, I Durán Merás, A Espinosa Mansilla, Anal. Chem. 76(2004)5657