QuEChERS Pretreatment Combined with Ultra-performance Liquid Chromatography–Tandem Mass Spectrometry for the Determination of Four Veterinary Drug Residues in Marine Products

Abstract

The extant methods for detecting multi-residues in aquatic products can avoid the disadvantages of complex pretreatment, long time consumption, single detection type, and low sensitivity. Therefore, developing a method that enables a multi-residue detection of veterinary drugs is very important. QuEChERS is a simple, rapid, and efficient method for detecting multi-drug residues. In this work, QuEChERS pretreatment combined with ultra-performance liquid chromatography–tandem mass spectrometry was proposed to identify sulfamide, tetracycline, quinolone, and malachite green residues in oyster, scallop, squid, and cuttlefish. The sample was extracted by using acetonitrile solution containing 0.1% acetic acid, while the extract was purified by using the QuEChERS method. The target analytes were separated on an ACQUITY UPLC BEH chromatographic column by using acetonitrile solution as a mobile phase for the gradient elution. Quantification was performed by using the internal standard method. The recovery of the 21 tested compounds was within the range of 65.26 to 113.5% and the relative standard deviation was less than 6.78%, thereby proving the good repeatability of the method. The intra- and inter-day precisions were less than 6.26% and 6.02%, respectively, while the limits of detection and quantification were less than 0.8 μg/kg and 2.5 μg/kg, respectively. The proposed method was then applied to detect residues in 150 samples of oysters, scallops, squid, and cuttlefish obtained from eight regions, including Shenzhen, Dongguan, Zhaoqing, Shantou, Maoming, Jiangmen, Shanwei, and Huizhou in Guangdong Province. No residues were detected in any of these samples. In sum, the proposed detection method has good reproducibility, high sensitivity, and reliability.