A method for simultaneous determination of multi-class antibiotics and steroid hormone analysis in faeces of livestock and poultry was developed using liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOF MS). An in-house database was built for 156 detected drugs using Personal Compound Database Library software (PCDL) including compound name, monoisotopic mass, chemical formula, RT, chemical structure and three CID MS/MS spectra. The linearity result showed that all the drugs exhibited good linearity with determination coefficients (R2) higher than 0.99. The drug recoveries and their RSDs for all three faeces samples (pig, cattle and chicken) were tested and 81, 96 and 92 drugs were chosen for analysis in pig, cattle and chicken faeces, respectively. Further validation showed that 73 veterinary drugs in all three kinds of faeces samples can be quantified in one analytical run. This work shows that qualitative and quantitative analysis using LC-QTOF MS represents a simple, sensitive, low-cost and high-throughput methodology in routine laboratory analyses.
Keywords: Time-of-flight mass spectrometry; antibiotics; livestock and poultry faeces; quantitative analysis; steroid hormones.