Simultaneous determination of 21 sulfonamide residues in seawater by UPLC-MS/MS

The UPLC-MS/MS method has been developed for the simultaneous determination of 21 sulfonamide residues in seawater.The samples were extracted with ethyl acetate,dried by an evaporator.The residues were dissolved into 1 mL mobile phase.The 21 compounds were separated on ACQUITYTM BEH C18 column with the mobile phase containing methanol and 5 mmol/L ammonium acetate(1% formic acid),and finally determined by electrospray ionization tandem mass spectrometry(ESI-MS/MS).The detection limits were lower than 0.5 ng/L,the quantitative limits were lower than 1.0 ng/L,the average recoveries were 70%～95%,RSDs were lower than 12%.