Development of a Competitive Indirect Enzyme-Linked Immunosorbent Assay for Screening Phenylethanolamine A Residues in Pork Samples

Phenylethanolamine A (PEA), a new alternative β-agonist, has been illegally used in farming to promote the muscle growth in food-producing animals. In this study, a sensitive and convenient competitive indirect enzyme-linked immunosorbent assay (ciELISA) was developed for determination of PEA residues in pork samples. The produced antibody was highly specific to PEA and exhibited a negligible cross-reactivity toward some other β-agonists. The developed technique was characterized by the limit of detection below 0.08 μg kg^?1 and the IC₅₀ value of 0.93 pmol mL^?1 (0.32 ng mL^?1). Validation of the technique was done using artificially spiked and naturally contaminated pork samples. The recoveries ranged from 79.6 to 112.6 % for the samples spiked at levels of 0.1–5 μg kg^?1 with the variation coefficients below 15 %. The analysis of naturally contaminated samples showed that the obtained data corresponded with the data obtained by the LC-MS/MS. The developed ciELISA was shown to be a feasible highly sensitive and specific screening tool for PEA residue analysis.