RESUMEN
Objective:To establish a method for the content uniformity ( CU) of fennel oil in Weitongning tablets to study the CU of fennel oil in Weitongning tablets. Methods: Methyl salicylate as the internal reference, the content of trans-anethole in fennel oil was determined by GC. The separation was performed on a DB-FFAP capillary column (30 m × 0. 32 mm, 0. 25 μm) at 145℃, the injection part temperature was 180℃ and the FID detector temperature was 230℃, nitrogen with high purity was used as the carrier gas at the flow rate of 0. 8 ml·min-1 . The air flow rate was 400 ml·min-1 and that of hydrogen was 35 ml·min-1 . The methodology validation was carried out, and the samples from different companies with different batches were determined. Results:Significant differ-ence showed in the CU of fennel oil in the samples with different batches from the same manufacturer or from different companies. The trans-anethole showed linear correlation within the range of 2. 189-35. 030 μg · ml-1 ( r =0. 999 9 ) and the average recovery was 100. 06% (RSD=0. 5%, n=9). Conclusion:The method is simple and quick. It is accurate in the CU determination of fennel oil and can be used for the quality control of Weitongning tablets.