Iowa State University Veterinary Diagnostics Laboratory provides diagnostic and analytical services for animal species, running roughly ~97K tests annually. Their mission is to ensure the health and welfare of livestock in both the state and in the United States. Since they provide testing for clients who may have different reasons (testing animals for export, show animals, animals to be sold) or time frames to receive the results, turning results around quickly and with high accuracy is of paramount importance.
The laboratory has performed both screening and quantitation for testing of veterinary drug residues in bovine muscle matrix. Figure 1 shows the chemical classes of veterinary drugs analyzed in the method, along with the number of compounds in each class. For this analysis, the method needed to cover a wide range of Maximum Residue Limits (MRLs) from 0.1 to 1000 ng/g in the bovine muscle matrix. Figure 2 and Figure 3 provide screening and quantitation results.
Figure 1. 109 compounds were analyzed by Iowa State University on the Orbitrap Exploris 120 MS instrument.
Figure 2: Screening results: An example of fragment and library match results in Thermo Scientific™ TraceFinder™ software for a veterinary drug residue, Carazolol at 2.5 ng/g. The bottom image shows the peak for Carazolol is shown in full scan.
Figure 3: Quantitation results: To test the method, a Certified Reference Material (CRM) containing incurred residues in bovine muscle was analyzed. The Orbitrap Exploris 120 MS instrument achieves quantitation results in alignment with the CRM values.
“The Orbitrap Exploris 120 mass spectrometer allows us to react to emergency testing situations in a variety of matrices without having to do a lot of method development. This enables us to provide high-quality data for veterinary drug residue testing to our clients.” Dwayne Schrunk, Laboratory Manager of the Analytical Chemistry Services, Iowa State University
To learn more about Iowa State University’s impressions of the Orbitrap Exploris 120 MS instrument, I’d encourage watching this user highlight video.