Determination of Molar Mass Ratio of Sodium to Potassium in Yan Huning by HPLC-ELSD

OBJECTIVE To establish a general detection method for determination of the molar mass ratio of sodium to potassium in Yan Huning material. METHODS The determination method was developed on a SIELC Primesep A column(4.6 mm×250 mm, 5 μm), with water-acetonitrile-trifluoroacetic acid (400:600:2) as mobile phase at a flow rate of 1.0 mL·min^-1. The column temperature was maintained at 30℃ and detection was ELSD (drift tube temperature was 105℃ and carrier gas flow rate was 3.2 L·min^-1). RESULTS Excellent resolution was shown between the peaks of Yan Huning and sodium and potassium. Good linearity were demonstrated for sodium and potassium in the concentration range of 6.841 9-34.209 6 μg·mL^-1 and 10.749 8-53.748 7 μg·mL^-1 respectively. The average recovery rates were 100.1% (RSD=1.9%) and 98.5%(RSD=1.0%), respectively. CONCLUSION The method was simple, fast and economy, and can be applied in the detection for the molar mass ratio of sodium to potassium in Yan Huning material and provide reliable detection basis for its quality control.