Gas Chromatography-High-Resolution Mass Spectrometry-Based Method for the Simultaneous Determination of Organotin Compounds in Water

A gas chromatography-high-resolution mass spectrometry (GC-HRMS)-based method has been developed for the accurate and sensitive determination of nine organotin compounds in water: tetrabutyltin, tributyltin, dibutyltin, monobutyltin, triphenyltin, diphenyltin, monophenyltin, tricyclohexyltin, and dicyclohexyltin. Details on procedures for glassware treatment, sample conditioning, extraction, and derivatization are all provided. In situ derivatization with sodium tetraethylborate is employed to overcome difficulties associated with extracting ionic compounds into an organic solvent from an aqueous matrix. GC-HRMS conditions under selective ion monitoring mode and quality control criteria for the positive identification of analytes are presented. Linearity of response and minimal detectable limits are provided for each of the nine compounds, and the estimates of method limits of detection are 7–29 ng/L based on a 100-mL water sample. All GC-HRMS quantitative formulas for the calculation of internal standard recovery and recovery-corrected organotin concentration in unknown samples are provided. Method precision and accuracy are determined using spiked clean water samples as well as spiked seawater samples used in bioconcentration experiments.