Development and validation of a method for quantification of residual florfenicol in various tissues of broiler chicken by UPLC-MS/MS

Florfenicol is a chloramphenicol antibiotic that plays an essential role on bacteriostasis. Long-term use of florfenicol in livestock and poultry can cause immunetoxicity and reproductive toxicity and the consumption of animal-derived products with excessive residues of florfenicol will pose a certain threat to human health. To study residue depletion of oral florfenicol in chickens, 48 healthy 30 -day -old AA broilers received continuous administration of 150 mg/kg/d florfenicol for five days. Muscle, liver, kidney and sebum were collected at 0.16, 1, 3, 5, 7 and 9 days after discontinuation of the drug and detected by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Most previous studies have shown that acid hydrolysis is necessary for tissue sample extraction. However, the steps of acid hydrolysis are tedious and time-consuming. In this experiment, we tried to improve the solvent extraction method to simplify the pretreatment process and the effect of acid hydrolysis was further analyzed and compared. Using the WT1.4 software the withdrawal time in muscle, liver, kidney and sebum obtained by F-QuEChERS-AOAC 3202 method was 7.82, 0.06, 4.38, 13.71 days respectively while acid hydrolysis method were 8.89, 5.84, 5.39 and 9.65 days, respectively. To reduce the residues of florfenicol and ensure the safety of chicken products, it is recommended that chickens taking oral florfenicol should be subjected to a 14 -days withdrawal time.