HPLC-ED of low-molecular weight brominated phenols and tetrabromobisphenol A using pretreated carbon fiber microelectrode

摘要

Electrochemically pretreated carbon fiber microelectrode was used to develop a simple, fast and sensitive HPLC-ECD method for the determination of brominated phenols. In addition to simple mono-,di-and tri-bromophenols （4-bromophenol, 2,4-dibromophenol,2,6-dibromophenol, 2,4,6-tri-bromophenol) the possibility of electrochemical detection of 3,3',5,5'-tetrabromobisphenol A in oxidation mode is reported for the first time. The isocratic separation was achieved within 14 min using ternary mobile phase consisting of 50 mM-phosphate buffer (pH 3,5),acetonitrile and methanol (35/15/50,v/v),and detection potential of E= + 1450 mV (vs. Ag/AgCl). The carbon fiber microelectrode permitted to use high anodic potentials (up to +1800 mV vs. Ag/AgCl), the optimum analytical response was achieved at +1450 mV vs. Ag/AgCl. The limits of detection (LOD) for the studied analytes were within the range of 1.8-56.6 ng mL~(-1). The developed method was applied to determination of brominated phenols in spiked water samples. Furthermore, after simple extraction with methyl tert-butyl ether, it was possible to quantify tetrabromobisphenol A (TBBA) in a piece of CRT monitor plastic casing. The found amount of TBBA was 10.22 mgkg~(-1) (± 0.43).