Determination of Scopolamine Hydrobromide and Total Alkaloid in Jiedukang Tincture

OBJECTIVE To establish an HPLC method for determination of contents of scopolamine hydrobromide and total alkaloid in Jiedukang tincture. METHODS A Diamonsil C18 column(250 mm×4.6 mm, 5 μm) was used to isolate and determine scopolamine hydrobromide. The mobile phase was methanol-0.02 mol·L^-1 NaAc solution (with 0.02% triethylamine and 0.3% tetrahydrofuran, adjusted to pH 6.2 by HAc). The flow rate was 1 mL·min^-1. The detection wavelength was set at 206 nm. Total alkaloids in Jiedukang tincture were determined with acid dye colorimetry. 0.2% Bromothymol blue was used as the dye reagent and the wavelength was set at 420 nm. RESULTS The linear range of scopolamine hydrobromide was 1.0-5.0 μg with a good correlation (r=0.999 6). The average recoveries was 98.8% with RSD of 2.29%(n=6). The total alkaloids showed good linearity within the range of 0.04-0.2 mg(r=0.999 8), the average recoveries was 97.6% with RSD of 2.06%(n=6). CONCLUSION The method established is sensitive, accurate and can be used for determination of scopolamine hydrobromide in Jiedukang tincture.