RESUMEN
XueBiJing is an intravenous five-herb injection used to treat sepsis in China.The study aimed to develop a liquid chromatography-tandem mass spectrometry(LC-MS/MS)-or liquid chromatography-ultraviolet(LC-UV)-based assay for quality evaluation of XueBiJing.Assay development involved identifying marker constituents to make the assay therapeutically relevant and building a reliable one-point cali-brator for monitoring the various analytes in parallel.Nine marker constituents from the five herbs were selected based on XueBiJing's chemical composition,pharmacokinetics,and pharmacodynamics.A selectivity test(for"similarity of response")was developed to identify and minimize interference by non-target constituents.Then,an intercept test was developed to fulfill"linearity through zero"for each analyte(absolute ratio of intercept to C response,＜2％).Using the newly developed assays,we analyzed samples from 33 batches of XueBiJing,manufactured over three years,and found small batch-to-batch variability in contents of the marker constituents(4.1％-14.8％),except for senkyunolide I(26.5％).