HPLC Analysis of Milk Thistle Standards on Ascentis^® Express C18

column

Ascentis Express C18, 10 cm x 3 mm I.D., 2.7 μm particles (53814-U)

mobile phase

[A] water with 0.1% formic acid; [B] methanol

gradient

held at 35% B for 3 min; 35 to 45% B in 10 min; held at 45% B for 2 min; 45 to 100% B in 5 min

flow rate

0.6 mL/min

pressure

4105 psi (283 bar)

column temp.

35 °C

detector

UV, 254 nm

injection

20 μL

sample

20 μg/mL in 80:20, water:methanol