HPLC Analysis of Withania Standards on Discovery^® C18

column

Discovery C18, 25 cm x 4.6 mm I.D., 5 μm particles (504971)

mobile phase

[A] 1 mM potassium phosphate, monobasic; [B] acetonitrile

gradient

5 to 45% B in 18 min; 45 to 80% B in 7 min; held at 80% B for 3 min

flow rate

1.5 mL/min

pressure

220 bar (3200 psi)

column temp.

27 °C

detector

UV, 227 nm

injection

20 μL

sample

20 μg/mL in water: acetonitrile (86:14)