Abstract
The application of micellar electrokinetic capillary chromatography for the separation and determination of the active ingredients in peanut shells is reported. The effects of several factors such as the pH and concentration of the running buffer, separation voltage, injection time, and the potential applied to the working electrode were investigated to find the optimum conditions. Six compounds were well separated using a fused silica capillary (56.8 cm length and 25 µm diameter) in 20 mM borax solution with 30 mM sodium dodecyl sulfate (pH 9.24). A carbon disk electrode (0.3 mm) was used as the working electrode and exhibited a good response at +1.006 V (vs. saturated calomel electrode) for the analytes operated in a wall-jet configuration. Excellent linearity was obtained over three orders of magnitude, and the detection limits were between 4 × 10−7 and 2 × 10−8 g mL−1. This method was successfully applied to the rapid analysis of peanut shells. The concentrations of chlorogenic acid and luteolin in the peanut shells were 3.849 × 10−4 g mL−1 and 6.314 × 10−3 g mL−1, respectively, which was in accordance with the results from other methods.