title: Application of a fully integrated photodegradation-detection flow-batch analysis system with an on-line preconcentration step for the determination of metsulfuron methyl in water samples.
abstract: This work presents the development of a fully automated flow-batch analysis (FBA) system as a new approach for on-line preconcentration, photodegradation and fluorescence detection in a lab-constructed mixing chamber that was designed to perform these processes without sample dispersion. The system positions the mixing chamber into the detection system and varies the instrumental parameters according to the required photodegradation conditions. The developed FBA system is simple and easily coupled with any sample pretreatment without altering the configuration. This FBA system was implemented to photodegrade and determine the fluorescence of the degradation products of metsulfuron methyl (MSM), a naturally non-fluorescent herbicide of the sulfonylurea׳s family. An on-line solid phase extraction (SPE) and clean up procedure using a C18 minicolumn was coupled to the photodegradation-detection mixing chamber (PDMC) that was located in the spectrofluorometer. An enrichment factor of 27 was achieved. Photodegradation conditions have been optimized by considering the influence of the elution solvent on both the formation of the photoproduct and on the fluorescence signal. Under optimal conditions, the calibration for the MSM determination was linear over the range of 1.00-7.20 µg L(-1). The limit of detection (LOD) was 0.28 µg L(-1); the relative standard deviation was 2.0% and the sample throughput for the entire process was 3h(-1). The proposed method was applied to real water samples from the Bahía Blanca׳s agricultural region (Bahía Blanca, Buenos Aires, Argentina). This method obtained satisfactory recoveries with a range of 94.7-109.8%.
authors.affiliation: INQUISUR (UNS-CONICET), Department of Chemistry, National University of the South, 1253 Alem Avenue, B8000CPB Bahía Blanca, Argentina. Electronic address: cacebal@uns.edu.ar.
authors.forename: Carolina C
authors.initials: CC
authors.lastname: Acebal
authors.affiliation: INQUISUR (UNS-CONICET), Department of Chemistry, National University of the South, 1253 Alem Avenue, B8000CPB Bahía Blanca, Argentina.
authors.forename: Marcos
authors.initials: M
authors.lastname: Grünhut
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, Charles University, 500 05 Hradec Králové, Czech Republic.
authors.forename: Ivana
authors.initials: I
authors.lastname: Srámková
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, Charles University, 500 05 Hradec Králové, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Chocholouš
authors.affiliation: INQUISUR (UNS-CONICET), Department of Chemistry, National University of the South, 1253 Alem Avenue, B8000CPB Bahía Blanca, Argentina.
authors.forename: Adriana G
authors.initials: AG
authors.lastname: Lista
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, Charles University, 500 05 Hradec Králové, Czech Republic.
authors.forename: Hana
authors.initials: H
authors.lastname: Sklenářová
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, Charles University, 500 05 Hradec Králové, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Solich
authors.affiliation: INQUISUR (UNS-CONICET), Department of Chemistry, National University of the South, 1253 Alem Avenue, B8000CPB Bahía Blanca, Argentina.
authors.forename: Beatriz S Fernández
authors.initials: BS
authors.lastname: Band
mesh_terms: D001190:Arylsulfonates / Q000032:analysis*; D002138:Calibration; D055772:Green Chemistry Technology; D006540:Herbicides / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D008027:Light; D057230:Limit of Detection; D010777:Photochemistry / Q000379:methods*; D010782:Photolysis; D015203:Reproducibility of Results; D052616:Solid Phase Extraction; D013050:Spectrometry, Fluorescence; D013453:Sulfonylurea Compounds / Q000032:analysis; D014867:Water / Q000737:chemistry*; D014873:Water Pollutants / Q000032:analysis
chemical_list: D001190:Arylsulfonates; D006540:Herbicides; D013453:Sulfonylurea Compounds; D014873:Water Pollutants; D014867:Water; C050296:metsulfuron methyl
keywords: Flow-batch analysis; Fluorescence; Metsulfuron methyl; On-line solid phase extraction; Photoinduced degradation