title: New method for the determination of metolachlor and buprofezin in natural water using orthophthalaldehyde by thermochemically-induced fluorescence derivatization (TIFD).
abstract: Herbicide metolachlor (MET) and insecticide buprofezin (BUP) were determined in natural waters by means of a newly-developed, simple and sensitive thermochemically-induced fluorescence derivatization (TIFD) method. The TIFD approach is based on the thermolysis transformation of naturally non-fluorescent pesticides into fluorescent complex O-phthalaldehyde-thermoproduct(s) in water at 70°C for MET and at 80°C for BUP. The TIFD method was optimized with respect to the temperature, pH, complex formation kinetic and pesticides concentrations. The limit of detection (LOD=0.8ngmL(-1) for MET and 3.0ngmL(-1) for BUP) and quantification (LOQ=2.6ngmL(-1) for MET and 9.5 ngmL(-1) for BUP) values were low, and the relative standard deviation (RSD) values were small (between 1.2% and 1.8%), which indicates a good analytical sensitivity and a great repeatability of TIFD method. Recovery studies were performed on spiked well, sea and draining waters samples collected in the Niayes area by using the solid phase extraction (SPE) procedure. Satisfactory recovery results (84-118%) were obtained for the determination of MET and BUP in these natural waters.
authors.affiliation: Laboratoire de Photochimie et d'Analyse (LPA), Faculté des Sciences et Techniques, Université Cheikh Anta Diop, BP 5005 Dakar, Sénégal.
authors.forename: Alphonse
authors.initials: A
authors.lastname: Mendy
authors.affiliation: Laboratoire de Photochimie et d'Analyse (LPA), Faculté des Sciences et Techniques, Université Cheikh Anta Diop, BP 5005 Dakar, Sénégal; Unité de Chimie Environnementale et Interactions sur le Vivant (UCEIV), ULCO, BP 59140 Dunkerque, France. Electronic address: thiaredienediegane@yahoo.fr.
authors.forename: Diène Diégane
authors.initials: DD
authors.lastname: Thiaré
authors.affiliation: Laboratoire de Photochimie et d'Analyse (LPA), Faculté des Sciences et Techniques, Université Cheikh Anta Diop, BP 5005 Dakar, Sénégal.
authors.forename: Souleymane
authors.initials: S
authors.lastname: Sambou
authors.affiliation: Laboratoire de Photochimie et d'Analyse (LPA), Faculté des Sciences et Techniques, Université Cheikh Anta Diop, BP 5005 Dakar, Sénégal.
authors.forename: Abdourahmane
authors.initials: A
authors.lastname: Khonté
authors.affiliation: Laboratoire de Photochimie et d'Analyse (LPA), Faculté des Sciences et Techniques, Université Cheikh Anta Diop, BP 5005 Dakar, Sénégal. Electronic address: tanoucoly@gmail.com.
authors.forename: Atanasse
authors.initials: A
authors.lastname: Coly
authors.affiliation: Laboratoire de Photochimie et d'Analyse (LPA), Faculté des Sciences et Techniques, Université Cheikh Anta Diop, BP 5005 Dakar, Sénégal.
authors.forename: Mame Diabou
authors.initials: MD
authors.lastname: Gaye-Seye
authors.affiliation: Unité de Chimie Environnementale et Interactions sur le Vivant (UCEIV), ULCO, BP 59140 Dunkerque, France.
authors.forename: François
authors.initials: F
authors.lastname: Delattre
authors.affiliation: Laboratoire de Photochimie et d'Analyse (LPA), Faculté des Sciences et Techniques, Université Cheikh Anta Diop, BP 5005 Dakar, Sénégal.
authors.forename: Alphonse
authors.initials: A
authors.lastname: Tine
mesh_terms: D000081:Acetamides / Q000032:analysis* / Q000737:chemistry; D002138:Calibration; D005618:Fresh Water / Q000032:analysis / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D015203:Reproducibility of Results; D012623:Seawater / Q000032:analysis / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D013696:Temperature; D013829:Thiadiazines / Q000032:analysis* / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis*; D009764:o-Phthalaldehyde / Q000737:chemistry*
chemical_list: D000081:Acetamides; D013829:Thiadiazines; D014874:Water Pollutants, Chemical; C083997:buprofezin; D009764:o-Phthalaldehyde; C051786:metolachlor
keywords: Buprofezin; Metolachlor; O-phthalaldehyde; Thermochemically-induced fluorescence derivatization; Water analysis