Second-Order Advantage Achieved with Four-Way Fluorescence Excitation-Emission-Kinetic Data Processed by Parallel Factor Analysis and Trilinear Least-Squares. Determination of Methotrexate and Leucovo

详细信息    查看全文

• 作者：Alejandro C. Olivieri ; Juan A. Arancibia ; Arsenio Muñ ; oz de la Peñ ; a ; Isabel Durá ; n-Merá ; s ; and Anunciació ; n Espinosa Mansilla
• 刊名：Analytical Chemistry
• 出版年：2004
• 出版时间：October 1, 2004
• 年：2004
• 卷：76
• 期：19
• 页码：5657 - 5666
• 全文大小：225K
• 年卷期：v.76,no.19(October 1, 2004)
• ISSN：1520-6882

文摘

Four-way fluorescence data recorded by following thekinetic evolution of excitation-emission fluorescencematrices (EEMs) have been analyzed by parallel factoranalysis and trilinear least-squares algorithms. Thesemethodologies exploit the second-order advantage of thestudied data, allowing analyte concentrations to be estimated even in the presence of an uncalibrated fluorescentbackground. They were applied to the simultaneousdetermination of the components of the anticancer combination of methotrexate and leucovorin in human urinesamples. Both analytes were converted into highly fluorescent compounds by oxidation with potassium permanganate, and the kinetics of the reaction was continuouslymonitored by recording full EEM of the samples atdifferent reaction times. A commercial fast scanningspectrofluorometer has been used for the first time tomeasure the four-way EEM kinetic data. The rapid scanning instrument allows the acquisition of a complete EEMin 12 s at a wavelength scanning speed of 24 000 nm/min. The emission spectra were recorded from 335 to490 nm at 5-nm intervals, exciting from 255 to 315 nmat 6-nm intervals. Ten successive EEMs were measuredat 72-s intervals, to follow the fluorescence kinetic evolution of the mixture components. Good recoveries wereobtained in synthetic binary samples and also in spikedurine samples. The excitation, emission, and kinetic timeprofiles recovered by both chemometric techniques arein good agreement with experimental observations.