Simultaneous Determination of Five β-Lactam Antibiotics in Bovine Milk Using Liquid Chromatography Coupled with Electrospray Ionization Tandem Mass Spectrometry

Abstract

A multiresidue method for the detection of five important beta-lactam antibiotics (amoxicillin, ampicillin, cloxacillin, oxacillin, penicillin G) in fresh milk is presented that allows quantitation of the analytes well below established legislative limits. The method avoids the use of acid during the extraction procedure and entails a cleanup step over a C18 cartridge. The analytes are separated and detected by liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) using a stable isotope-labeled internal standard. Mass spectral acquisition is done in the positive ion mode by applying selected reaction monitoring of two or more fragmentation transitions per analyte to provide a high degree of sensitivity and specificity. The typical recoveries for all five beta-lactams in fresh milk ranged from 76 to 94% at a fortification level of 4 microg/kg. This study also addresses common problems encountered in the stability of penicillins during sample preparation as well as the employment of postcolumn infusion of a standard compound to verify potential matrix-induced signal suppression in ESI-MS.

Determination of penicillin G and its degradation products in a penicillin production wastewater treatment plant and the receiving river

“…We have set the cone voltage from 20 to 80 V at an interval of 20 V, and the maximum structural information was obtained at 60 V for all the analytes except for penilloic acid and penicilloaldehyde, which were obtained at 80 V as shown in Table 1. It has been reported that fragmental ions of PEN G were m/z 160 and 176 in the positive ion mode (Riediker and Stadler, 2001), and m/z 192 and 289 in the negative mode (Becker et al, 2004) using LC-ESI/MS/MS. In this study, fragmental ions were found to be m/z 192 and 289 for PEN G, the same as that reported using LC-ESI/MS (Straub and Voyksner, 1993).…”

Simultaneous Determination of Residual Veterinary Drugs in Bovine, Porcine, and Chicken Muscle Using Liquid Chromatography Coupled with Electrospray Ionization Tandem Mass Spectrometry

“…Several methods have been reported for the simultaneous determination of veterinary drugs in muscle. [3][4][5][6][7][8][9][10] Most of these methods were developed with the intention of determining analogous compounds, [5][6][7][8][9][10][11][12][13][14] and there are scarcely any reports on methods developed with the intention of simultaneous determination of compounds belonging to various classes. Liquid chromatography coupled with electrospray ionization tandem mass spectrometry (LC/MS/MS) affords a highly specific method of determining various compounds by providing structural information.…”

Preparation and Application of Core-Shell Structural Carbon Nanotubes-Molecularly Imprinted Composite Material for Determination of Nafcillin in Egg Samples

“…There is a constant requirement for accurate, sensitive and selective analytical methods for monitoring nafcillin antibiotic residues to guarantee the safety of food. Usually, the complexity of food matrices and contaminants presented in food at low concentration (ng g -1 to ȝg g -1 ) levels require analysis performance only after some clean-up and preconcentration steps [2][3][4] , and thus there is a considerable interest in developing new specific and selective methods for extracting and isolating components from complex food matrices. For this purpose, the solid phase extraction (SPE) technique is the most widely used for sample pre-treatment method due to its advantages such as convenience, low cost, timing saving and simplicity.…”