the mobile phase , with a flow-rate of 1.5 ml/min , contained various amounts of acetonitrile ( 25-40 % , v/v ) , 5 % ( v/v ) 0.2 m ammonium phosphate buffer ph 6.5 , 20 % ( v/v ) 0.2 m tetramethylammonium phosphate and water .
C0051724
ammonium phosphate
C0031603
phosphate