Screening procedures for clenbuterol residue determination in raw swine livers using lateral-flow assay and enzyme-linked immunosorbent assay.

Clenbuterol, which may cause symptoms of increased heart rate, muscular tremors, headache, nausea, and muscular cramps in patients, has been prohibited for consumption in many countries including the European Union, the United States, and China. A rapid lateral-flow strip assay was developed in our laboratory, and results obtained with this assay were compared with those obtained with a commercial enzyme-linked immunosorbent assay (ELISA) kit for the screening of clenbuterol in raw swine liver. A total of 128 swine livers were acquired from five local markets and prepared for analysis by the lateral-flow strip assay and ELISA. Analysis was completed in 10 min with the lateral-flow strip assay and in 90 min with the ELISA. In parallel with the ELISA, the rapid detection strip produced no false-negative results but had a false-positive rate of 6.3%. Cross-reactivity of the strip was assessed and was negative after tests with clenbuterol analogues such as terbutaline, salbutamol, ractopamine, ritodrine, and fenoterol. These data suggest that a lateral-flow strip assay can be used safely as a screening method as part of a clenbuterol residue surveillance program and should be a valuable tool in the food safety field, especially in developing countries.