Submitted to: ACS Food Science and Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/29/2021
Publication Date: 12/15/2021
Citation: Shelver, W.L., Chakrabarty, S., Smith, D.J. 2021. A rapid screening method for ß-adrenergic agonist residues incurred in animal urine using direct analysis in real time mass spectrometry (DART-MS). ACS Food Science and Technology. 2:195-205. https://doi.org/10.1021/acsfoodscitech.1c00427.
Interpretive Summary: Beta-agonists can be used as feed additives to promote animal growth and as therapeutic agents to treat asthma. Because of the importance of ß-agonists in food safety, medicine, trade, and competition, their use is often monitored by food-safety regulatory agencies, importers/exporters, and competition organizers. We developed an analytical method using a technique called “direct analysis in real time” mass spectrometry to simultaneously analyze 4 ß-agonists in animal urine. The method we developed has the potential to save money and time and to provide adequate sensitivity for the rapid screening of animal exposure to ß-agonists.
Technical Abstract: 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, laboratory supply costs and overall time of analysis. This study was designed to determine the usefulness of DART-MS for the rapid detection and semi-quantitation of the ß-agonists clenbuterol, ractopamine, salbutamol and zilpaterol in cow, horse, and sheep urine. Samples were mixed with 10% sodium carbonate followed by extraction with ethyl acetate and applied to a 96-grid DART mesh prior to analyses. Total DART-MS analysis time was approximately 45 min per 96-grid plate. 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 (LOQs) 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 deviation (RSDs) of all four standards fortified in cow, horse and sheep urine were between 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 zilpaterol in horse (R2 = 0.73) and sheep urine (R2 = 0.59). The study demonstrates the utility of DART-MS for rapid screening of multiple ß-agonists in urine matrices with very little sample preparation.