INFIQC   05475
INSTITUTO DE INVESTIGACIONES EN FISICO- QUIMICA DE CORDOBA
Unidad Ejecutora - UE
artículos
Título:
Cucurbit[6]uril nanocavity as an enhanced spectrofluorimetric method for the determination of pyrene
Autor/es:
VALERIA N. SUELDO OCCELLO; ALICIA V. VEGLIA*
Revista:
ANALYTICA CHIMICA ACTA
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Año: 2009 vol. REDA
ISSN:
0003-2670
Resumen:
Trabajo en redacción al 31.12.09 Trabajo enviado a publicar el 09.02.10 Trabajo en revisión para ser reenviado de acuerdo a la opinión del Editor Abstract The effect of the addition of the macrocyclic host cucurbit[6]uril (CB6) on the photophysical properties of the polycyclic aromatic hydrocarbon pyrene (PYR) was investigated. The fluorescence emission spectra of the aromatic compound were determined at 25.0 ºC in different acidic media (HCl 18 % w/v or HCOOH 55 % w/v) with and without CB6. A significant enhancement in the fluorescence signals in the presence of CB6 at room temperature was observed. The values of the association constant (KA) for the 1:1 stoichiometry complex and the relative fluorescence quantum yield ratio between the complexed and free PYR (f PYR-CB6/f PYR) in HCl 18 % (w/v) were (4.4 ± 0.2) ´ 102 M-1 and (5.5 ± 0.2), respectively. The analytical parameters improved in the presence of CB6. The relative decrease in the limit of detection was 92 %. The matrix effect was evaluated in fortified samples of tap water and tea extracts. Apparent recoveries obtained by the proposed method in tap water and tea extracts were (82-103) % and (89-99) %, respectively. Selectivity studies with inorganic and organic species were performed. The method is rapid, direct, selective and simple.