IQUIR   05412
INSTITUTO DE QUIMICA ROSARIO
Unidad Ejecutora - UE
artículos
Título:
Determination of folic acid and its two main metabolites in serum by on line photochemically induced excitation-emission-kinetic four-way data
Autor/es:
JIMENEZ GIRON, A.; DURAN MERAS, I.; ESPINOSA MANSILLA, A.; MUNOZ DE LA PENA, A.; CAÑADA CAÑADA, F.; OLIVIERI, A. C.
Revista:
ANALYTICA CHIMICA ACTA
Editorial:
Elsevier
Referencias:
Lugar: Amsterdam; Año: 2008 vol. 622 p. 94 - 103
ISSN:
0003-2670
Resumen:
<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> The determination of folic acid and its two main serum metabolites, 5-methyltetrahydrofolic acid and tetrahydrofolic acid, has been accomplished using four-way data modelled by the third-order multivariate calibration methods Unfolded and N-dimensional Partial Least-Squares (U-PLS and N-PLS), in combination with the separate procedure known as Residual Trilinearization (RTL). The four-way data were acquired by following the photochemical reaction of these compounds by on line irradiation with a UV lamp. The excitation-emission matrices (EEMs) were recorded as a function of the irradiation time, using a fast scanning spectrofluorimeter. The method achieves selectivity from the different rates at which the corresponding photoproducts of the folic acid derivatives are formed and degraded. Several N-dimensional chemometric algorithms were used and the method was applied to the determination of these compounds in serum samples. The best algorithms to perform the multivariate calibration were U-PLS and N-PLS in combination with the separate Residual Trilinearization procedure, achieving the second-order advantage. The approach allows minimizing or eliminating traditionally time-consuming sample pre-treatments and can facilitate quantifying an analyte in its native environment.