Submitted to: International Association for Food Protection
Publication Type: Abstract Only
Publication Acceptance Date: 3/26/2022
Publication Date: 8/2/2022
Citation: Shelver, W.L., Chakrabarty, S., Smith, D.J. 2022. A rapid screening method for ß-adrenergic agonist residues incurred in animal urine using direct analysis in real time mass spectrometry (DART-MS). International Association for Food Protection. Abstract.
Technical Abstract: Introduction: Direct analysis in real time mass spectrometry (DART-MS) works at atmospheric pressure without lengthy, labor-intensive sample preparation or chromatographic separation of analytes. Consequently, DART-MS reduces labor, most laboratory supply costs, and overall time of analysis. Purpose: To determine the usefulness of DART-MS for the rapid detection (screening) and semi-quantitation of clenbuterol, ractopamine, salbutamol and zilpaterol, ß-agonists used as feed additives or veterinary therapeutics, in cow, horse, and sheep urine. Methods: Samples were mixed with 10% sodium carbonate, extracted with ethyl acetate, and applied to a 96-grid DART mesh prior to DART-MS analyses. Matrix matched calibration curves were used to extrapolate the ß-agonist concentrations in incurred urine samples. Results: The coefficient of determination of standard curves for the compounds in cow, horse and sheep urine ranged from 0.9930 to 0.9986, 0.9829 to 0.9990, and 0.9925 to 0.9997, respectively. Limits of quantitation for clenbuterol, ractopamine, salbutamol and zilpaterol ranged from 4.0 to 239.7, 29.5 to 551.3 and 6.9 to 205.2 ng/mL in cow, horse, and sheep urine, respectively. The inter-day relative standard deviations of standards fortified in cow, horse and sheep urine were 26.3 to 33.4, 23.9 to 41.1 and 30.7 to 37.0%, respectively. Moderate correlations were measured between DART-MS and LC-MS/MS data for incurred zilpaterol residues in horse (R2 = 0.73) and sheep urine (R2 = 0.59). Significance: The study demonstrates the utility of DART-MS for rapidly screening four commonly screened ß-agonists in urine matrices with very little sample preparation.