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Determination of Sulfonamides in Bovine Milk by Ultra Performance Liquid Chromatography Combined with Quadrupole Mass Spectrometry

A novel method has been developed for the rapid separation and determination of 24 Sulfonamides (SAs) in bovine milk by using ultra-performance liquid chromatography tandem quadrupole mass spectrometry (UPLC-MS/MS) in ten minutes. Sulfonamides residues from bovine milk were treated with acetonitrile, followed by homogenizing, ultrasound treating, and centrifuging. The aforementioned procedure is repeated one additional time. A part of the extracts was taken to dryness and defatted twice. The analysis was performed on an Acquity UPLCTM BEH C18 column under the mobile phase which is composed of 0.2% acetic acid in water and acetonitrile. The analytes were detected by multiple reaction monitoring (MRM) in the positive ion scan mode. The calibration curves showed acceptable linearity in the concentration range from 0.2 to 100 ng mL−1 with correlation coefficients (r2) above 0.992. The mean recoveries of 24 SAs in different standard-spiked levels were in the range of 60.59–116.66%; RSD% was 2.92%∼18.64%. Results showed analytical category, separation speed, selectivity, sensitivity, and repeatability of sulfonamides in milk using UPLC-MS/MS that were significantly improved compared to other analytical methods.