The illegal use of clenbuterol seriously endangers food safety and human health. Accurate monitoring of the illegal use of clenbuterol in livestock can efficiently prevent the clenbuterol residue pork products from entering the consumer market. Thus, in this study, a simple, rapid, and sensitive method for the determination of clenbuterol in swine urine was developed using electromembrane extraction combined with liquid chromatography-tandem mass spectrometry. It should be noted that the electromembrane extraction method presented many advantages of simple operation, fast mass transfer rate, good sample clean-up capability, and less organic solvent consumption. The effect of important factors on the extraction efficiency of clenbuterol was investigated. Under the optimal conditions, good linearity was achieved for clenbuterol over the range of 1–1000 ng/ml (linear correlation [ R 2 ] = 0.9996). The recoveries of clenbuterol in swine urine at three spiked levels ranged from 83.7% to 110.0% with relative standard deviation values lower than 9.7% ( n = 4). The limits of detection and quantification for clenbuterol were 0.07 and 0.25 ng/ml, respectively. These results suggested that the proposed method has great potential for the extraction and determination of trace analyte in a complex sample matrix for monitoring illegal use in livestock.
In this work, amido-functionalized Fe3O4 microspheres (AFFMs) were loaded in network-structured MnO2 to form a nanocomposite named as OAM. OAM could remove chlortetracycline hydrochloride (CTC) and trivalent arsenic (As(III)) simultaneously from swine urine aqueous solution and soil. Therein, OAM has a high adsorption capability for CTC through hydrogen bonds. Additionally, OAM could effectively adsorb As(III) through electrostatic attraction and then oxidize it to pentavalent arsenic (As(V)). Afterward, the resulting OAM/CTC/As could be conveniently removed with a magnet. When OAM was deposited on the surface of a piece of cotton fabric (CF), the obtained OAM/CF could efficiently control the migration of CTC and As(III) in a sand–soil mixture. Importantly, OAM could effectively reduce the uptake of CTC and As by zebrafish, water spinach, and pakchoi, and promote the growth of water spinach. Finally, OAM possessed good biosafety for embryos of Caenorhabditis elegans. Thus, this work provides a new method to remove CTC and As(III) simultaneously in swine urine aqueous solution and soil, which may have a high application value.
危险品化学品经营许可证（带存储）