Application of Gas Chromatography–Atomic Fluorescence Spectrometry Hyphenated System for Speciation of Butyltin Compounds in Water Samples

Abstract

ABSTRACT A laboratory-established capillary gas chromatography (GC)–atomic fluorescence spectrometry (AFS) hyphenated system was applied to butyltin speciation in water samples. Monobutyltin (MBT), dibutyltin (DBT), and tributyltin (TBT) were extracted and preconcentrated with headspace solid-phase microextraction (SPME) technique after derivatization using KBH4, and then determined by GC-AFS directly. The experimental conditions—including the flow rates of carrier gas, argon and hydrogen–and the lamp current—were optimized in detail. Under the optimum conditions, the detection limits for MBT, DBT, and TBT, calculated as three times the baseline noise, were 10, 0.2, and 0.1 ng mL−1 Sn, respectively. Good linear relationships were obtained when the concentrations of MBT, DBT, and TBT increased to 3000, 100, and 200 ng mL−1 Sn. The relative standard deviations (RSDs) of five replicates were 5.2%, 7.4%, and 7.1% for MBT, DBT, and TBT, respectively. The recoveries of MBT, DBT, and TBT in three different types of water samples (seawater, tap water, and wastewater) were between 72.1% and 97.9%, indicating that the proposed method was accurate and feasible for speciation analysis of butyltin compounds in water samples.