Quantitative Determination of Alkaloids from Roots of Hydrastis canadensis L. and Dietary Supplements Using Ultra-Performance Liquid Chromatography with UV Detection

Ultra-performance liquid chromatography (UPLC) with UV detection was used for the quantification of alkaloids from roots of Hydrastis canadensis L. (goldenseal) and dietary supplements claiming to contain goldenseal. The analysis was performed on a Waters Acquity UPLC system with an Acquity UPLC BEH Shield RP18 column using gradient elution with ammonium formate and acetonitrile containing formic acid. The chromatographic run time was less than 6 min. The detection wavelength used for β-hydrastine and canadine was 290 nm; for hydrastinine, coptisine, jatrorrhizine, palmatine, and berberine, it was 344 nm. A total of five different extraction solvents, including 100% methanol, 90% methanol, 90% methanol + 1% acetic acid, 90% acetonitrile + 0.1% phosphoric acid, and 100% acetonitrile, were tested for recovery of the major compounds. The samples extracted with the 90% methanol + 1% acetic acid displayed the best recovery (>97%). The analytical method was validated for linearity, repeatability, LOD, and LOQ. The RSDs for intraday and interday experiments were less than 3.5%, and the recovery was 98–103%. UPLC/MS with a quadrupole mass analyzer and electrospray ionization source was used to confirm the identity of seven alkaloids. The analytical method was successfully applied to confirm the identification of seven alkaloids from the roots of H. canadensis, dietary supplements that claimed to contain goldenseal, and possible adulterant species.