Confirmatory analysis of β‐lactam antibiotics in kidney tissue by liquid chromatography/electrospray ionization selective reaction monitoring ion trap tandem mass spectrometry

Abstract

Eleven beta-lactam antibiotics were analyzed in fortified and incurred beef kidney tissue using high-performance liquid chromatography/electrospray ionization/selective reaction monitoring-ion trap tandem mass spectrometry (LC/ESI-SRM-MS(n)). The analytes included: deacetylcephapirin, amoxicillin, cephapirin, desfuroylceftiofur cysteine disulfide (DCCD, a biomarker of ceftiofur), ampicillin, cefazolin, Pen G, oxacillin, cloxacillin, naficillin and dicloxicillin. Analytes were extracted with acetonitrile and water. Clean-up was performed by solid-phase extraction. Limits of confirmation in fortified tissue are as follows (tolerances or target levels in parentheses): deacetylcephapirin: 10-50 ng/g (100 ng/g); amoxacillin: 50-100 ng/g (10 ng/g); cephapirin: 10 ng/g (100 ng/g); DCCD: 500 ng/g (8000 ng/g); ampicillin: 10 ng/g (10 ng/g); cefazolin: 10 ng/g (10-50 ng/g); Pen G: 10 ng/g (50 ng/g); oxacillin: 10 ng/g (10-50 ng/g); cloxacillin: 10 ng/g (10 ng/g); naficillin: 10 ng/g (10-50 ng/g); dicloxacillin: 100-500 ng/g (10-50 ng/g). The present method was also tested on incurred kidney tissue that had previously been analyzed using a microbial assay. Good correspondence was found between the results from this new method and the bioassay. However, the present method is much more specific and, in several cases, more sensitive than the bioassay. In addition, the time of analysis is significantly shorter than the bioassay. We also found that SRM MS(n) was superior in the analysis of unknown incurred tissue than full spectrum MS(n). We also obtained an MS/MS spectrum of DCCD that is significantly at variance with previously published fragmentation spectra.

Rapid method for the quantification of amoxicillin and its major metabolites in pig tissues by liquid chromatography-tandem mass spectrometry with emphasis on stability issues

“…Moreover, it is reported that the use of organic solvents should be avoided during extraction of penicillins due to degradation [33]. The use of ion-pairing reagents, like tetraethylammonium chloride [20] for extraction was not advisable in combination with LC-MS/MS analysis, since they can produce unacceptable levels of chemical noise on the mass spectrometer using electrospray ionization [29]. Bogialli et al [31] used water of 65 • C as extractant at a pH of 3 and stated a recovery of almost 90% for AMO and AMPI in tissue samples.…”

“…In the literature combinations of sulphuric acid and sodium tungstate solutions [17,21] are reported for deproteinisation of tissue samples. Others used high volumes of organic solvents like acetonitrile [4,20,29,30], methanol [19,32] or iso-octane [24] (up to >25 ml). Moreover, it is reported that the use of organic solvents should be avoided during extraction of penicillins due to degradation [33].…”

“…1, together with their MS and MS/MS traces, obtained by infusing of a standard solution of 1 g ml −1 in combination with the LC-flow. Most publications for the quantitative determination of AMO with LC-MS/MS also used the positive ionization mode [4,10,11,[25][26][27][28][29][30][31]. Yoon et al [34] reported the negative ionization mode for AMO for the quantification of the antibiotic in human plasma with an LOQ of 120 ng ml −1 .…”

“…There are methods reported to extract AMO from animal tissues followed by HPLC with UV [17][18][19][20][21], fluorimetric [22][23][24][25] and mass spectrometric detection [4,10,11,[26][27][28][29][30][31][32], but only one LC-MS/MS assay is involved with the simultaneous determination of AMO and its major metabolites [10].…”

Quechers methodologies as an alternative to solid phase extraction (SPE) for the determination and characterization of residues of cephalosporins in beef muscle using LC–MS/MS

“…In particular, LC-MS or LC/MS/MS are the preferred techniques in the determination of ␤-lactams residues. A number of authors have reported multiresidue methods for the determination of ␤-lactams in animal tissues or milk [6,[9][10][11][12][13][14][15][16][17], but only a few of these methods include some cephalosporins as targets of study [9][10][11]16,17].…”