Development of a new method for the enantiomer specific determination of HBCD using an ion trap mass spectrometer

An alternative method for the enantiomer specific determination of hexabromocyclododecanes (HBCD) by LC-ESI-MS/MS using an ion trap analyser is proposed. The method is based on the formation of a chlorine adduct (m/z 676.6) of the (+/-)alpha-, (+/-)beta-, and (+/-)gamma-HBCD enantiomers and their further fragmentation into their stable quasi-molecular ion (m/z 640.6). In this way, problems related to the ion trap low mass cutoff and variable amounts of other adduct peaks in the samples are solved. Parameters affecting separation, ionisation and MS/MS detection were studied. Method performance was also evaluated: calibration curves were found linear from 20 to 400 pg mu L-1 for each enantiomer; detection limits ranged between 1.5 and 4.3 pg mu L-1; repeatability and reproducibility, expressed as relative standard deviation, were lower than 6% and 13%, respectively The application to different types of spiked samples (pork meat, lean fish, and butter) pointed out the occurrence of matrix effects that could be solved by using labelled standards. (c)) 2007 Elsevier B.V. All rights reserved.