Simultaneous Analysis of four Nitrofurans and Chloramphenicol Antibiotics in Seawater and Fisheries water using LC-MS/MS

A simultaneous analysis of four nitrofurans (NFs) and chloramphenicol (CAP) in seawater and water for aquaculture, was performed using solid-phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS).The detection of NFs and CAP in seafood is prohibited by the Agricultural Products Quality Control Act and the Food Sanitation Act in Korea as well as in the EU and USA.Types of SPE cartridges, optimal pH conditions in water samples, and mobile phases of LC were tested and selected.Target antibiotics were ionized in positive mode for furazolidone and furaltadone and in negative mode for nitrofurantoin, nitrofurazone, and CAP.The HLB cartridge showed more stable recoveries (81-89%), compared to WAX and MCX.The extraction efficiency of the target antibiotics was more than 80% between a pH of 3 and 8. Lower the pH of the water samples, the more stable was their recovery.The mobile phase of ammonium formate and MeOH enhanced the resolution and sensitivity by five times compared with those in previous reports.Moreover, the retention time of the target compounds was accelerated, and the overall analytical time was reduced by 1/2.The accuracy and precision of the analytical method were 85-93% and 3-19%, respectively, and the recovery of internal standards was 83-88%.Instrumental detection limits were 0.18-1.02ng/L, and method detection limits and limits of quantification were 0.60-3.99ng/L and 1.92-12.7 ng/L, respectively, which were 20 times higher than those reported in previous studies.The optimized analytical method in the present study can be used as a proactive method for the detection of banned substances in water for aquaculture farms and seawater in coastal areas.