Separation Study of Eight Isoflavones by MEKC with Different Surfactants

Comparison of Phenolic Compound Separations by HPTLC and PPEC with SDS as the Mobile Phase Component

The application of the surfactant (sodium dodecyl sulphate, SDS) as the component of the water-organic mobile phase in thin-layer chromatography and pressurized planar electrochromatography is presented. The influence of various variables on the separation of various phenolic compounds (flavonoids and phenolic acids) as model compounds with systems containing surfactant is discussed. The effect of concentration of butanol and SDS as well as pH of the mobile phase buffer on migration distance of the solute zones is investigated. The presence of SDS in the eluent affects the butanol solubility in the mobile phase. It allows using higher organic solvent concentration systems compared with the mode without surfactant. The amount of SDS in the eluent has the effect on the solute retention, whereas the eluent buffer pH affects the migration distances of ionisable phenolic acids both in HPTLC and PPEC. The migration distances of flavonoid glycosides are considerably longer than those of pure flavonoids. Considering second group of investigated solutes, derivatives of the benzoic acid migrate longer distances in comparison with the cinnamic acid ones. In addition, in the majority of experiments, ionisable compounds (phenolic acids) migrate longer distances in PPEC than nonionisable compounds (flavonoids). Additionally, the order of solutes differs in the PPEC and HPTLC system.

Simultaneous separation and determination of praeruptorin A, B and C by micellar electrokinetic chromatography using sodium dodecyl sulphate and sodium cholate as mixed micelles

INTRODUCTION

Praeruptorin A, B and C are major bioactive constituents in Peucedani Radix. They display anti-inflammatory effect, anti-hypertension effect, antiplatelet aggregation, potential anti-cancer activities and so on. They are worthy of investigation as potentially novel and versatile drugs.

OBJECTIVE

To develop a method using micellar electrokinetic chromatography (MEKC) for the application in simultaneously separation and determination of praeruptorin A, B and C from Peucedani Radix and its medicinal preparations.

METHODS

Method optimisation was carried out by investigating influences of significant factors on the separation. The method was subjected to validation. The determination of praeruptorin A, B and C in Peucedani Radix and its drug formulations was accomplished by the developed method.

RESULTS

The optimal separation condition was 20 mM borate buffer containing 40 mM sodium cholate (SC), 22 mM sodium dodecyl sulphate (SDS) and 25% (v/v) acetonitrile (pH 10.00); 15 kV of voltage; 25°C of temperature; detection at 224 nm. Under this condition, three analytes were baseline separated within 16 min. A good linearity was obtained with correlation coefficients from 0.9988 to 0.9995. The limits of detection (LODs) and limits of quantitation (LOQs) ranged from 0.50 to 0.80 μg/mL and from 1.50 to 2.50 μg/mL, respectively. The recoveries ranged between 95.3% and 103.4%.

CONCLUSION

The proposed method has been successfully applied to the simultaneous determination of praeruptorin A, B and C in Peucedani Radix and its pharmaceutical preparations. Additionally, it could be a potential alternative to the quality control of Peucedani Radix.