Column:

GP C18 ( 5 µm, 120 Å, 4.6 x 250 mm )

Mobile phase:

Phosphate buffer pH 5.0 ( KH₂PO₄ 2.0g dissolved by about 650mL water, add 15mL 0.5mol/L tetrabutylammonium hydroxide in methanol, 7mL1mol/L H₃PO₄ solution and 270mL methanol, cool to room temperature, adjust to pH 5.0 by NH₃·H₂O, then dilute to 1000mL by water )

Flow rate:

1.2 mL/min

Column temperature:

25 ℃

Detection:

UV 280 nm

Injection volume:

10 µL