the ion pairs were labelled with dansylhydrazine and the hydrazones were separated by hplc on a capcell-pak c8 ( silicone polymer-coated silica gel modified with octyl groups ) reversed-phase column using methanol-0.5 % ( w/v ) sodium acetate-50 % ( v/v ) acetic acid ( 57:42:1 , v/v/v ) as the mobile phase .
C0142785
sodium acetate
C0000983
acetic