[Application of high performance liquid-ion trap mass spectrometry in analyzing saponins in sodium aescinate]

Sodium aescinate, which is produced from saponins of Chinese Buckeye Seed, is a prescription drug for treatment of brain edema and all kinds of swellings caused by surgery. In this article, high-performance liquid chromatography/ion trap (HPLC-IT) mass spectrometry was applied to study the characteristic ions of ten reference substances, namely escin Ⅰa, escin Ⅰb, isoescin Ⅰa, isoescin Ⅰb, aesculiside A, aesculiside B, aesculuside A, escin Ⅳc, escinⅡa and escin Ⅴ, which were isolated from aescinate. Furthermore, 19 saponin compounds were predicted in sodium aescinate, besides the above mentioned reference substances. The study showed that sapogenins in sodium aescinate had two structural types, namely protoaescigenin and barringenol C, and the substituent acetyl, tigloyl or angeloyl was usually located at C-21, C-22 or C-28 position. Among these predicted saponins, their sugar chains were all located at C-3 position consisting of glucose and glucuronide. This study provides experimental data for chemical constituents in sodium aescinate and scientific basis for quality and safety evaluation.