Table 2. MRM parameters in MS/MS for fipronil and its metabolites

Pesticide Molecular formula Retention time (min) Precursor ions (m/z) Product ions (m/z) Cone voltage (V) Collision energy (eV)
Fipronil (F) C12H4C12F6N4OS 1.96 436.50 330.50 20 15
250.20 20 30
Fipronil desulfinyl (FD) C12H4C12F6N4 2.76 387.29 351.29 25 17
282.31 25 26
Fipronil sulfide (FS) C12H4C12F6N4S 3.69 418.91 262.35 20 15
383.57 20 28
Fipronil sulfone (FSO) C12H4C12F6N4O2S 2.85 450.29 415.31 22 27
282.27 22 17