title: Simultaneous determination of carbaryl and o-phenylphenol residues in waters by first-derivative synchronous solid-phase spectrofluorimetry.
abstract: A spectrofluorimetric method for the simultaneous determination of carbaryl (CBL) and o-phenylphenol (OPP) residue mixtures in waters has been developed. Carbaryl was hydrolysed in alkaline medium to give 1-naphthol. This compound and o-phenylphenol were fixed on QAE Sephadex A-25 gel at pH 10.75. The fluorescence of the gel, packed in a 1-mm silica cell, was measured directly with a solid-surface attachment. Overlapping of conventional fluorescence spectra is resolved by using first-derivative synchronous spectrofluorimetry and allows for the complete resolution of the mixture. The range of application is between 0.4 and 25.0 ng/ml for OPP and 0.8 and 25.0 ng/ml for CBL. The detection limits for o-phenylphenol and carbaryl were 0.1 and 0.2 ng/ml, respectively. The accuracy and precision of the method are reported. The method is suitable for determination of carbaryl and o-phenylphenol residues in natural waters. Recoveries from 95 to 105% have been obtained for natural waters spiked with CBL and OPP.
authors.affiliation: Department of Analytical Chemistry, University of Granada, E-18071 Granada, Spain.
authors.forename: L F
authors.initials: LF
authors.lastname: Capitán-Vallvey
authors.forename: J
authors.initials: J
authors.lastname: Rohand
authors.forename: A
authors.initials: A
authors.lastname: Navalón
authors.forename: R
authors.initials: R
authors.lastname: Avidad
authors.forename: J L
authors.initials: JL
authors.lastname: Vilchez