Extraction Strategies for Simultaneous Determination of Florfenicol and Florfenicol Amine in Tilapia (Oreochromis niloticus) Muscle: Quantification by LC-MS/MS

A liquid chromatography-tandem mass spectrometry method was developed and validated for the simultaneous determination of the veterinary drug florfenicol (FF) and its major metabolite, florfenicol amine (FFA), in tilapia muscles (Oreochromis niloticus). Three different sample preparation procedures (DLLME, sub-zero, and modified QuEChERS) were tested. The best extraction results were obtained by using the modified QuEChERS. The quantification was made by using a LC-MS/MS analysis, with a Lichrocart Cartridge Purospher Star C-8 HPLC column (250 mmx4.6 mm, 5 mu m particle size). Analytes were separated with a mobile phase consisting of Milli-Q water to acetonitrile 40:60 (v/v), both with 0.1% formic acid. The validation parameters were recovery of 70 to 79% and 62 to 69%, limit of detection of 0.0625 mu g g(-1) and 0.125 mu g g(-1), and limit of quantification of 0.125 mu g g(-1) and 0.25 mu g g(-1), for FF and FFA, respectively. CC alpha was 1183 mu g kg(-1) and CC beta was 1365 mu g kg(-1) for FF, intraday and interday precision has CV <= 20%, and linear range was 0.625 to 5.00 mu g g(-1). This method was shown to be simple and rapid when compared to other, more conventional methods. Also, it has low reagent and solvent consumption, with low waste generation, which is in line with the principles of green chemistry. The method was successfully applied for the analyzes of tilapia exposed to the antibiotic.