LC-MS/MS Method, Development and Validation to Determine Three Tetracyclines and Their Epimers in Shrimp Samples

A modest liquid chromatography/tandem mass spectrometric method was developed and validated to determine three tetracycline antibiotics and their epimers tetracycline, oxytetracycline, chlortetracycline, 4-epi tetracycline, 4-epi oxytetracycline, 4-epi chlortetracycline in shrimp samples respectively. The procedure was involved the extraction of tetracyclines and its epimers from homogenized sample with EDTA-McIlvaine buffer followed by solid phase extraction clean up with Oasis HLB cartridge. The analysis was carried out using Inertsil ODS-3V, 5 micron, 150×4.6 mm column and mobile phase consists of 5 mM Oxalic acid in water (A) and 0.1% formic acid in methanol (B) in gradient mode at a flow rate of 0.8 mL/minutes. The final extracts were analyzed by the sensitive and selective LC/ESI/MS/MS operating in positive ion multiple reaction monitoring (MRM) mode.