Simultaneous determination of 120 veterinary antibiotics in meat by combined pretreatment system coupled with ultra-performance liquid chromatography-tandem mass spectrometry

A comprehensive pretreatment system was developed to simultaneously extract and purify 120 veterinary antibiotics, possessing various physicochemical properties in eight categories. This system was coupled with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for the detection of the antibiotics. The samples were dissolved and dispersed by a Na(2)EDTA-Mcllvaine buffer, extracted with acetonitrile containing 1. 5% (v/v) formic acid, and cleaned using an Oasis PRiME HLB SPE system followed by n-hexane liquid purification. The separation of residue targets was performed on an Atlantis T3 column (100 mmx2. 1 mm, 3 m) with a gradient elution of 0. 1% (v/v) formic acid aqueous solution and acetonitrile as mobile phases and detected by UPLC-MS/MS with the multiple reaction monitoring (MRM) mode via Esr ionization. The pH of the extraction solvent and the purification method were optimized to promote the target recoveries. All targets showed good linear ranges from 1. 0 to 50. 0 mu g/L, while all their correlation coefficients (r(2)) were higher than 0. 995 3, including r(2) values of 89 targets being over 0. 999 0. The limits of quantification (LOQs) of seven targets were 10. 0 mu g/kg; 21 targets, 5. 0 g/kg; and the remaining 92 targets, not higher than 2. 0 g/kg. The average recoveries on three spiked levels (low, medium, and high) for all targets ranged from 71. 5% -109. 2%, with RSD ranging from 0. 6% -15. 3%. The combined system, exhibiting satisfying recovery and stable repeatability, can be suitably employed for the simultaneous determination of multiple veterinary antibiotics in animal -derived meat products.