Native vs photoinduced chemiluminescence in dimethoate determination.
Anal Chim Acta
; 710: 81-7, 2012 Jan 13.
Article
en En
| MEDLINE
| ID: mdl-22123115
The determination of dimethoate using either its native chemiluminescent (CL) properties or its photoinduced chemiluminescence obtained by irradiation with a 15 W low-pressure mercury lamp was studied. Thereby, two flow injection systems (FIA) with and without irradiation were exhaustively optimized and their analytical characteristics studied. Better sensitivity and selectivity was found in absence of irradiation, due to the enhancing effect of hexadecylpyridinium chloride (HPC), which acted as a sensitizer. In the developed FIA-CL system, the alkaline hydrolysis of dimethoate with NaOH was performed on-line in presence of HPC. The oxidation of the product of hydrolysis with Ce(IV) in hydrochloric medium induced chemiluminescence. The method provided a limit of detection of only 0.05 ng mL(-1) without any pre-treatment. However, the combination with solid phase extraction allowed the removal of some potential interferents as well as the preconcentration of the pesticide. Finally, the developed method was successfully applied to natural waters with recoveries between 95 and 108%.
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1
Colección:
01-internacional
Base de datos:
MEDLINE
Idioma:
En
Revista:
Anal Chim Acta
Año:
2012
Tipo del documento:
Article
País de afiliación:
España
Pais de publicación:
Países Bajos