Optimization of the Extraction Conditions and Simultaneous Quantification by RP-LC of Six Alkaloids in Evodiae Fructus

A reversed phase liquid chromatographic (LC) method coupled with DAD (250 nm) has been developed and validated for simultaneous quantification of six alkaloids, dehydroevodiamine (1), wuzhuyuamide-I (2), 5-hydroxyrutaecarpine (3), 14-formyldihydrorutaecarpine (4), evodiamine (5) and rutaecarpine (6), in 12 batches evodiae fructus [the dried, unripe fruits of Evodia rutaecarpa (Juss.) Benth. or E. rutaecarpa (Juss.) Benth. var. officinalis (Dode) Huang, E.rutaecarpa (Juss.) Benth. var. bodinieri (Dode) Huang] as a traditional Chinese medicine. The method was carried out by a C18 column (250 × 4.6 mm) with a gradient mobile phase of methanol, acetonitrile, and phosphoric acid–triethylamine–buffer solution. The contents of 1–6 in the evodiae fructus could easily be determined within 70 min. The experimental results were satisfactory for the intra-day and inter-day precision and accuracy of the method for simultaneous determination. The linear calibration ranges of 1–6 were 40–1,000, 20–500, 1–100, 10–500, 40–1,000 and 80–1,000 μg mL−1. The recoveries of 1–6 were 97.43–103.73% with RSDs from 0.21 to 1.99%. The limits of detection for 1–6 were 2.0, 2.0, 0.1, 1.0, 5.0 and 5.0 μg mL−1, and the limits of quantification were 6.6, 6.6, 0.3, 3.3, 16.5 and 16.5 μg mL−1. The method was successfully applied to the quantification of six alkaloids in the evodiae fructus.