Environmental water samples analysis of pesticides by means of chemometrics combined with fluorimetric multioptosensing.
A single flow-through optosensor spectrofluorimetric system is proposed for the resolution of mixtures of three pesticides, alpha-naphthol, o-phenylphenol and thiabendazole, at microg l(-1) levels using a partial least-squares (PLS) calibration approach. The sensor was developed in conjunction with a monochannel flow-injection analysis system with fluorimetric detection using C18 silicagel as an active sorbent substrate in the flow cell. By using 20% methanol-water (v:v) solution as carrier solution, the multisensor responds linearly in the measuring range without requiring additional reagents or derivatization. First derivative emission spectra of the corresponding analytes recorded during the process of retention-elution were used to provide multivariate data. The different kinetic on the retention process of the analytes on the sensing zone allows the selection of a time matrix for each analyte providing best results in the PLS approach. Accurate prediction results were obtained for the three analytes with RMSEP values of 1.86%, 3.34% and 0.50% were obtained for alpha-naphthol, o-phenylphenol and thiabendazole respectively. In the analysis of environmental waters samples, a mean recovery of 103% was obtained.
Domínguez-Vidal
Ana
A
Department of Physical and Analytical Chemistry, Faculty of Experimental Sciences, University of Jaén, Campus Las Lagunillas, E-23071 Jaén, Spain.
Ortega-Barrales
Pilar
P
Molina-Díaz
Antonio
A
D001713:Biphenyl Compounds / Q000032:analysis* / Q000737:chemistry; D002138:Calibration; D005618:Fresh Water / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D016018:Least-Squares Analysis; D000432:Methanol / Q000737:chemistry; D009284:Naphthols / Q000032:analysis* / Q000737:chemistry; D010575:Pesticides / Q000032:analysis* / Q000737:chemistry; D015203:Reproducibility of Results; D012212:Rheology / Q000379:methods; D045483:Rivers / Q000737:chemistry; D058428:Silica Gel; D012822:Silicon Dioxide / Q000737:chemistry; D013050:Spectrometry, Fluorescence / Q000379:methods; D013827:Thiabendazole / Q000032:analysis* / Q000737:chemistry; D014873:Water Pollutants / Q000032:analysis*
D001713:Biphenyl Compounds; D009284:Naphthols; D010575:Pesticides; D014873:Water Pollutants; C029350:1-naphthol; D058428:Silica Gel; D012822:Silicon Dioxide; C004369:2-phenylphenol; D013827:Thiabendazole; D000432:Methanol