Chromatographic retention and mass spectrometric characteristics of hydroxylated and methoxylated polybrominated diphenyl ethers

Behaviors of eighteen hydroxylated polybrominated diphenyl ethers (HO-BDEs) and fifteen methoxylated polybrominated diphenyl ethers (MeO-BDEs) in chromatography and mass spectrometry were characterized. High performance liquid chromatography with diode array detector and mass spectrometric detector, and gas chromatography (GC) with electron capture detector (ECD) and electron ionization (EI) mass spectrometric detector were employed. Retention of MeO-BDEs in reversed phase liquid-chromatography was governed by hydrophobic interaction, while the retention of HO-BDEs was affected by other specific interactions besides hydrophobic interaction. Both of atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI) were used in LC/MS. LC/APCI-MS was suitable to detect HO-BDEs, while both of APCI and ESI gave no response to MeO-BDEs. The position of the hydroxy and methoxy substituent (ortho, meta and para) relatives to the diphenyl ether oxygen in HO-BDEs and MeO-BDEs determined the compositions of mass spectrometric fragments in EI-MS and APCI-MS.