Agriculture Reference
In-Depth Information
7.5 APPLICATION NUMBER 2: TARGETED AND NONTARGETED
SCREENING APPROACHES FOR THE IDENTIFICATION OF ANTIMICROBIAL
RESIDUES IN MEAT
In another example, we were able to demonstrate experimentally the reliability of
HRMS in the analysis of traces of veterinary medicinal products in foodstuffs of
animal origin (Figure 7.3). This project was mainly focused on screening meat
products for different families of antimicrobials that are authorized in the EU. Starting
from a method we developed on an LC
MS/MS system and dedicated to multianti-
biotic monitoring in meat tissues and in milk [29], this LC
-
-
HRMS method was
implemented using an LTQ
Orbitrap mass spectrometer, a hybrid MS instrument
with a linear trap hyphenated to an orbital trap [30].
A standard sample mixture of 60 antibiotics from different families was prepared at
or close to their MRLs and then subjected to LC
-
-
HRMS analysis. From the resulting
LC
-
HRMS raw data (i.e., TIC), we identi
ed all the antibiotics, which were subjected
to LC
HRMS analysis, by extracting the ion chromatogram of each antibiotic at their
respective exact masses and the value of the retention time was recorded. These values
-
LC-HRMS in full scan mode
Targeted approach
Known compounds
Nontargeted approach
Unknown compounds
Comparison of two groups (control and
incurred) by statistical tools
Screening for compounds from a list of
target ions
Showing a list of
ions of interest
Identification based on retention time and
exact mass
(relative to a reference substance)
Complementary analysis to identify the
chemical structure of compounds of
interest
Figure 7.3.
Comparison of a targeted approach against a nontargeted approach.
