Objective: This article aimed to to study the main pharmacodynamic substances of pediatric compound preparation Xiefei Pingchuanling by serum pharmacochemistry. Method: UPLC-LTQ-Qrbitrap technology was used to create fingerprints of both compound extract and rat serum after treatment. Then the peaks were compared and predicted to belong to which single herb and their constituents were inferre. Result: 18 transitional ingredients in Xiefei Pingchuanling were detected and identified in rat serum

10 of which could be directly absorbed into the bloodstream by the body;the 8 remaining prototype components may be new ingredients produced through metabolism. Conclusion: UPLC fingerprint provides much medicinal information in plasma of rats treated with Xiefei Pingchuanling

therefore

it is of great value to studies on the metabolism of traditional Chinese medicine (TCM).