Objective: To establish the verified method of gas chromatography (GC) characteristic chromatogram of volatile components in Zhengtian pills

and provide a reference for the quality control of this preparation. Method: Volatile components in 16 batches of Zhengtian pills were extracted by steam distillation and analyzed by GC

taking relative retention time as index

GC characteristic chromatogram of volatile components in Zhengtian pills was established

difference of characteristic chromatogram between Zhengtian pills and 14 batches of intermediate was investigated. Result: Twenty common peaks were selected as characteristic peaks to assess similarities of different samples from different origins

and three of them were confirmed.Relative standard deviations (RSDs) of precision

reproducibility

stability were all less than 0.1%.RSDs of relative retention time of common peaks in intermediate were less than 0.1%

and threre was little difference between intermediate and Zhengtian pills. Conclusion: This method is accurate and reliable with good repeatability

which can be used for quality control of volatile components in Zhengtian pills.Preparation technology of Zhengtian pills is stable and its consistency between batches is good.