Analysis of hydroxylated polybrominated diphenyl ethers in rat plasma by using ultra performance liquid chromatography-tandem mass spectrometry.

Ultra performance liquid chromatography (UPLC) provides improved resolution, speed and sensitivity compared to conventional high performance liquid chromatography (HPLC). In this study, a robust UPLC-ESI-MS/MS method was developed for the rapid determination of nine hydroxylated polybrominated diphenyl ethers (OH-PBDEs) in rat plasma. Under the optimized conditions, the OH-PBDE congeners were eluted within 7.0 min. The limits of quantification defined at the signal-to-noise ratio of 10 were 0.17-2.78 ng/mL in rat plasma. The method provided good linearity for the calibration curves with recoveries of 93.3-114.0% and repeatability with relative standard deviation (RSD) of 0.6-5.8% for intra-day and 3.2-10.4% for inter-day measurements. The developed method was applied for supporting the pharmacokinetics investigation of 6-OH-BDE-47 in two groups of Sprague-Dawley rats that received, respectively a single dose of 0.60 mg/kg (high dose) and 0.15 mg/kg (low dose) by intravenous injection. The results showed that plasma levels of 6-OH-BDE-47 declined bi-exponentially with elimination half-life of 71.7 and 85.6 min for lower and higher dose group, respectively. The obtained results of short elimination half-life suggested that 6-OH-BDE-47 might not accumulate significantly in rat.