Determination of Nuciferine, Rutin and Hyperoside in PlumulaNelumbinis by Capillary Electrophoresis with End-column Amperometric Detection

A method based on capillary electrophoresis with end-column amperometric detection (CE-AD) was developed for the determination of Nuciferine, Rutin and Hyperoside in Plumula Nelumbinis. The working electrode was a 500 μm diameter carbon disc electrode positioned opposite the outlet of capillary. The pH and concentration of running buffer, separation voltage, injection time and detection potential were investigated to acquire the optimum conditions. The three analytes could be well separated within 15 min in a 60 cm length capillary ( 25 μm×370 μm) at a separation voltage of 15 kV in a 50 mmoL/L Na₂B₄O₇-100 mmoL/L NaH₂PO₄ running buffer (pH=7.25). The detections limit for Nuciferine, Rutin and Hyperoside is 0.02 μg/mL, 0.05 μg/mL and 0.04 μg/mL, respectively. The optimized CE-AD method was employed to analyze Nuciferine, Rutin and Hyperoside in Plumula Nelumbinis, and the assay results are satisfactory.