0.996). The method was validated to be reproducible and reliable, as evidenced by intra-batch and inter-batch precision of less than 10% and 11%, accuracy of 97.13%-106.05% and 99.22%-103.14%, respectively. The recovery of extraction ranged from 72.74% to 89.13%, matrix effect from 88.76% to 105.97% for four catechins. The method was successfully used to study the pharmacokinetics of TP iv administered to rats at a dose of 100 mg/kg. Conclusion This method is shown to completely meet requirements for the multi-component pharmacokinetic study of TP in rats."/>