Analysis of Veterinary Drug Residues in Frog Legs and Other Aquacultured Species Using Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry

Abstract

A liquid chromatography quadrupole time-of-flight (Q-TOF) mass spectrometry method was developed to analyze veterinary drug residues in frog legs and other aquacultured species. Samples were extracted using a procedure based on a method developed for the analysis of fluoroquinolones (FQs) in fish. Briefly, the tissue was extracted with dilute acetic acid and acetonitrile with added sodium chloride. After centrifugation, the extracts were evaporated and reconstituted in mobile phase. A molecular weight cutoff filter was used to clean up the final extract. A set of target compounds, including trimethoprim, sulfamethoxazole, chloramphenicol, quinolones, and FQs, was used to validate the method. Screening of residues was accomplished by collecting TOF (MS¹) data and comparing the accurate mass and retention times of compounds to a database containing information for veterinary drugs. An evaluation of the MS data in fortified frog legs indicated that the target compounds could be consistently detected at the level of concern. The linearity and recoveries from matrix were evaluated for these analytes to estimate the amount of residue present. MS/MS data were also generated from precursor ions, and the mass accuracy of the product ions for each compound was compared to theoretical values. When the method was used to analyze imported frog legs, many of these residues were found in the samples, often in combination and at relatively high concentrations (>10 ng/g). The data from these samples were also evaluated for nontarget analytes such as residue metabolites and other chemotherapeutics.

Qualitative Screening of Undesirable Compounds from Feeds to Fish by Liquid Chromatography Coupled to Mass Spectrometry

“…Until now, LC-QTOF MS has been scarcely employed for monitoring the presence of organic contaminants in fish origin raw materials, fish and feed [23][24] . In fact, LC-MS techniques have not been used much for analysis of this type of fatty samples.…”

Atmospheric pressure ionization–tandem mass spectrometry of the phenicol drug family

“…Moreover, the Commission Decision 2002/657/EC, concerning the performance criteria for analytical methods for the analysis of veterinary residues in foods, established that confirmatory methods of banned substances such as CAP (group A) should be based on separation techniques coupled to mass spectrometry (MS), achieving the required identification points without the need of complementary chromatographic methods. As a result, confirmatory methods for the analysis of phenicols in foods are generally based on gas chromatography–MS and liquid chromatography–MS (LC‐MS) …”

Separation and determination of tetracycline hydrochloride in real water samples using binary small molecule alcohol‐salt aqueous two‐phase system coupled with high‐performance liquid chromatography

“…ATPS has some advantages, such as short processing time, gentle biocompatible environment, and no use of toxic volatile organic solvent in the experiment. Usual types of ATPS include two different polymers ATPS, polymer‐salt ATPS, ionic liquid (IL)‐salt ATPS, and small molecular water‐miscible organic solvent‐salt ATPS . The application of polymer‐polymer and polymer‐salt ATPS has been restricted as their shortcomings such as high viscosity, difficulty in phase separation, and easily emulsify.…”