Analysis of Sarcandra glabra and its medicinal preparations by capillary electrophoresis.

A simple, rapid, selective and reproducible capillary electrophoresis (CE) method was firstly developed for the identification and determination of isofraxidin and fumaric acid in a traditional Chinese herb Sarcandra glabra and its medicinal preparations. The buffer solution used in this method was 7.5 mM NaH2PO4 and 7.5 mM borax solution adjusted to pH 8.60. The linear calibration range was 1.25–800 μg ml−1 (r=0.9997) for isofraxidin and 10–800 μg ml−1 (r=0.9992) for fumaric acid, respectively. Under the optimum conditions, the relative standard deviation (R.S.D.) values of the migration time and the peak area were 0.47, 3.45% for isofraxidin and 0.83, 3.24% for fumaric acid, respectively. The recoveries ranged between 95.4–103.8% for isofraxidin and 97.1–104.7% for fumaric acid, respectively. The contents of isofraxidin and fumaric acid in Sarcandra glabra and two kinds of Sarcandra glabra-containing Chinese medicinal preparations were successfully determined within 8 min.