title: Salting-out assisted liquid-liquid extraction with the aid of experimental design for determination of benzimidazole fungicides in high salinity samples by high-performance liquid chromatography.
abstract: A novel method for the simultaneous separation and determination of four benzimidazole fungicides (i.e., carbendazim, fuberidazole, thiophanate-methyl and thiophanate) in high salinity samples was developed by using salting-out assisted liquid-liquid extraction (SALLE) via water-miscible acetonitrile as the extractant coupled with high-performance liquid chromatography. Box-Behnken design and response surface were employed to assist the optimization of SALLE conditions, including volume of salting-out solvent, the pH of sample solution and salting-out solvent as variable factors. The optimal salting-out parameters were obtained as follows: 2 mL of acetonitrile was added to 2 mL of sample solution with pH=4 and then 2 mL salting-out solvent containing 5 mol L(-1) sodium chloride at a pH of 7 was added to the solution for extraction. This procedure afforded a convenient and cost-saving operation with good cleanup ability for the benzimidazole fungicides, such as good linear relationships (R>0.996) between peak area and concentration from 2.5 ng mL(-1) to 500 ng mL(-1), low limits of detection between 0.14 ng mL(-1) and 0.38 ng mL(-1) and the intra-day precisions of retention time below 1.0%. The method recoveries obtained at fortified three concentrations for three seawater samples ranged from 60.4% to 99.1%. The simple, rapid and eco-benign SALLE based method proved potentially applicable for trace benzimidazole fungicides analysis in high salinity samples.
authors.affiliation: Key Laboratory of Coastal Zone Environmental Processes, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Beijing 100049, PR China.
authors.forename: Yingying
authors.initials: Y
authors.lastname: Wen
authors.forename: Jinhua
authors.initials: J
authors.lastname: Li
authors.forename: Fangfang
authors.initials: F
authors.lastname: Yang
authors.forename: Weiwei
authors.initials: W
authors.lastname: Zhang
authors.forename: Weiran
authors.initials: W
authors.lastname: Li
authors.forename: Chunyang
authors.initials: C
authors.lastname: Liao
authors.forename: Lingxin
authors.initials: L
authors.lastname: Chen
mesh_terms: D000097:Acetonitriles; D001562:Benzimidazoles / Q000032:analysis*; D002219:Carbamates / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D005659:Fungicides, Industrial / Q000032:analysis*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D057230:Limit of Detection; D059625:Liquid-Liquid Extraction / Q000379:methods*; D015203:Reproducibility of Results; D054712:Salinity; D012623:Seawater / Q000737:chemistry; D012997:Solvents; D013875:Thiophanate / Q000031:analogs & derivatives / Q000032:analysis*; D014867:Water; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D000097:Acetonitriles; D001562:Benzimidazoles; D002219:Carbamates; D005659:Fungicides, Industrial; D012997:Solvents; D014874:Water Pollutants, Chemical; D014867:Water; D013875:Thiophanate; C006698:carbendazim; C004198:fuberidazole; C032159:acetonitrile