title: Fast methodology for the reliable determination of nonylphenol in water samples by minimal labeling isotope dilution mass spectrometry.
abstract: In this work we have developed and validated an accurate and fast methodology for the determination of 4-nonylphenol (technical mixture) in complex matrix water samples by UHPLC-ESI-MS/MS. The procedure is based on isotope dilution mass spectrometry (IDMS) in combination with isotope pattern deconvolution (IPD), which provides the concentration of the analyte directly from the spiked sample without requiring any methodological calibration graph. To avoid any possible isotopic effect during the analytical procedure the in-house synthesized (13)C1-4-(3,6-dimethyl-3-heptyl)phenol was used as labeled compound. This proposed surrogate was able to compensate the matrix effect even from wastewater samples. A SPE pre-concentration step together with exhaustive efforts to avoid contamination were included to reach the signal-to-noise ratio necessary to detect the endogenous concentrations present in environmental samples. Calculations were performed acquiring only three transitions, achieving limits of detection lower than 100ng/g for all water matrix assayed. Recoveries within 83-108% and coefficients of variation ranging from 1.5% to 9% were obtained. On the contrary a considerable overestimation was obtained with the most usual classical calibration procedure using 4-n-nonylphenol as internal standard, demonstrating the suitability of the minimal labeling approach.
authors.affiliation: Research Institute for Pesticides and Water, Universitat Jaume I, E-12071 Castellón, Spain.
authors.forename: Neus
authors.initials: N
authors.lastname: Fabregat-Cabello
authors.forename: Ángel
authors.initials: Á
authors.lastname: Castillo
authors.forename: Juan V
authors.initials: JV
authors.lastname: Sancho
authors.forename: Florenci V
authors.initials: FV
authors.lastname: González
authors.forename: Antoni Francesc
authors.initials: AF
authors.lastname: Roig-Navarro
mesh_terms: D002247:Carbon Isotopes / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D007553:Isotope Labeling / Q000379:methods; D016014:Linear Models; D010636:Phenols / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D052616:Solid Phase Extraction; D053719:Tandem Mass Spectrometry / Q000379:methods*; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D002247:Carbon Isotopes; D010636:Phenols; D014874:Water Pollutants, Chemical; D014867:Water; C041594:4-nonylphenol
keywords: Isotope dilution mass spectrometry; Isotope pattern deconvolution; LC–MS/MS; Minimal labeling; Nonylphenol; Wastewater analysis