Investigation of sorption phenomena by solid phase extraction and liquid chromatography for the determination of some ether derivatives of tetrabromobisphenol A

Observed sorption and chromatographic behaviour served as a starting point for the examination of four ether derivatives of the flame retardant tetrabromobisphenol A (TBBPA): dihydroxyethyl (DHEE), dimethyl (DMe), diallyl (DAE) and dibromopropyl (DBPE). To date, there is little or no information about these compounds in the scientific literature. The targets in the present study had calculated log K-ow values of 6.0-10. A broad range of different types of solvents were used in order to elucidate the mechanisms of sorption onto silica (glass) and two solid phase extraction cartridges based on polystyrene divinylbenzene polymers, hydroxylated (Isolute ENV+) and vinylpyrrolidone (Oasis HLB) containing units. Also, three chromatographic columns (C18, C8 and dual C18-based, i.e. a polar ligand together with C18 on a silica surface) were evaluated. The following were observed: desorption of the targets from silica surface by 1-propanol showed the best results and the yields were further improved by silylation of the surface. Regardless of the experimental test conditions applied, the lowest recovery was seen for the DMe derivative, followed by TBBPA itself, which had calculated log K-ow values in between the other targets. A washing solution containing up to 70% methanol could be used without elution of the targets from the solid phase extraction cartridge. The dihydroxethyl ether derivative of TBBPA is most probably not affected by environmental relevant pH due to a likely high pK(a) (ca 15). Also, this study shows that the polar character of the dual-phase column was not as pronounced as asserted by the manufacturer. Copyright (C) 2009 John Wiley & Sons, Ltd.