Purification of icariin from the extract of Epimedium segittatum using high-speed counter-current chromatography.

Icariin was purified from the extract of Epimedium segittatum by high-speed counter-current chromatography with a two-phase solvent system composed of n-hexane-n-butanol-methanol-water (1:4:2:6, v/v). We used two multilayer coil planet centrifuges with different capacities. A 300 mg amount of the extract was separated using a semipreparative instrument equipped with a 230-ml capacity column to yield 103 mg of icariin at 86.2% purity. An 8 g amount of the extract was separated with a large preparative instrument equipped with a 2460-ml capacity column to produce 2.45 g of icariin at 85.7% purity. From these fractions over 98% pure icariin was obtained by recrystallization with water.