Investigation on metabolism and pharmacokinetics of triclosan in rat plasma by using UPLC-triple quadrupole MS

Triclosan has been widely used as a disinfectant in human health care products. Although this particular chemical is less toxic, its biotransformation products might have toxicity to human. Therefore, understanding the pharmacokinetics and metabolism of triclosan in animal and human body is important. Plasma samples from SD rats collected after the oral administration of 5 mg/kg triclosan were analyzed by ultra performance liquid chromatography (UPLC )-triple quadrupole mass spectrometry (TQMS) to support the pharmacokinetic study of triclosan. The method development was conducted with selected-ion-recording (SIR. also called SIM for selected-ion-monitoring) mode in ESI-MS and multiple-ion-monitoring (MRM) mode in MS/MS and the obtained results were compared. While MRM provided lower detection limits, its other method validation parameters were worse than those of SIR due to the poor fragmentation of triclosan. The developed SIR method provided limit of quantification of 10. 8 ng/mL in plasma. The recovery, accuracy, precision and repeatability were satisfactory. The pharmacokinetic data of triclosan in the rats were presented including the half time of elimination that was (48. 5 ± 10.5) h, indicating that the elimination of triclosan in the rat was slow. Two hydroxylated and sulfonated triclosan. one glucuronidated triclosan. and one sulfonated triclosan were identified in the rat plasma samples.