Quantitative determination of theanine in tea stalk by HPLC- ELSD
To estahlish a method for the determination of the content of in theanine using high-performance liquid chromatography with evaporative light scattering detector (HPLC-ELSD). HPLC-ELSD analysis was performed on AE. Lichrom C18 (250 mmx4.6 ram, 5 μm)with the mobile phase of 0.1% trifluoroacetic acid acetonitrile solution (A) and 0.1% trifluoroacetie acid water solution (B) (45:55). Drift tube temperature was 54 %, pressure of nebulizer gas was 1.46x10s Pa. The resolution of theanine was good. The linear calibration curves were obtained over the range of 2.55-20.43 μg. The average recovery of the method was 98.5% with RSD of 2.30%. This method is convenient, accurate and reliable. The tea stalk is still of great re-utilizable value.
NETL
NSTL
万方数据
维普
