Rapid Screening of β-Agonists in Animal Hair by Thermal Desorption Electrospray Ionization Mass Spectrometry

Even though the use of β-agonists in livestock has been banned in many countries, β-agonists abuse is still out of control owing to time-consuming and complicated determination techniques.

This study applied ambient thermal desorption electrospray ionization mass spectrometry (TD-ESI/MS) as a new strategy for rapidly screening seven β-agonists. As it does not require pretreatment, this method allows on-site and real-time detection.

Samples were collected directly using a simple metal probe. Analytes on the probe were desorbed and ionized by TD-ESI, after which analyte ions were detected using a triple quadrupole mass analyser.

The results showed that a thermal desorption temperature of 320°C and nebulizer pressure of 3 psi demonstrated the highest sensitivity. Excellent linear relationships were obtained in concentrations ranging from 10 to 400 μg/kg. The limit of detection of the method was 1-10 μg/kg with RSDs of 7.2-14.6%. A positive sample was verified using HPLC coupled with triple quadrupole tandem mass spectrometry, consistent with the results from TD-ESI/MS.

This method was the first to apply TD-ESI/MS to rapid analyse β-agonists in livestock hair and was proven to be accurate, fast, and environmentally friendly. Because qualitative screening for each analysis was completed within approximately 1 min, the method could contribute to preventing non-compliance in the flow of animal-derived food to the market.

This method was a promising method for the rapid screening of β-agonists in livestock hair at any time of breeding without imposing any harm to animal which proven to be a rapid, in situ, and non-destructive detection technique without any pretreatment.