Optimized Separation of Isoquinoline Alkaloids in Thalictrum Herbal Medicine by Microemulsion Electrokinetic Chromatography

Abstract Microemulsion electrokinetic chromatography (MEEKC), as a promising separation technique providing good selectivity and high efficiency, was used for the separation of seven isoquinoline alkaloids in Thalictrum plant. The optimized separation was studied with regard to pH, the compositions of a microemulsion system, the additions of organic solvents and sodium cholate (SC), applied voltage, and column temperature. The baseline separation was successfully achieved using the microemusion system at pH 8.0, consisting of 10 mM phosphate, 140 mM sodium dodecyl sulfate (SDS), 100 mM n‐heptane, 12% (v/v) n‐butanol, 1% (v/v) methanol, and 5 mM SC under 25 kV applied voltage and 25°C column temperature within 20 min. Meanwhile, the effects of variables on separation selectivity were discussed.