Determination of l-menthol in Qingxuanwan by callipary GC

[Purpose] To develop an GC method for content determination of l-menthol in Qingxuanwan. [Methods] The sample was determinated by GC after being extracted by ethanol with ultrasonic extractor. The GC-FID experiments were performed on an Aglient 6890N GC equipped with flame ionization detector (FID). DB-WAX column (30 m × 0.25 mm, 0.25μm) was used. The injector, column and detecto rtemperatures were 250°C, 160°C and 250°Crespectively. The samples were injected by split mode. The ratio of split was 5:1. The flow rate was 1.0 ml/min. The injection volume was 2 μl. [Results] The average recovery was 98.0% and RSD was 0.7%(n=6). [Conclusion] The method is proved to be sensitive and accurate, and can be used to control the quality of Qingxuanwan.