Rapid Determination of Ractopamine Residues in Edible Animal Products by Enzyme‐Linked Immunosorbent Assay: Development and Investigation of Matrix Effects

Abstract

To determine ractopamine residues in animal food products (chicken muscle, pettitoes, pig muscle, and pig liver), we established a rapid direct competitive enzyme-linked immunosorbent assay (ELISA) using a polyclonal antibody generated from ractopamine-linker-BSA. The antibody showed high sensitivity and specificity in phosphate buffer, with an IC50 of 0.6 ng/mL, and the limit of detection was 0.04 ng/mL. The matrix effect of the samples was easily eliminated by one-step extraction with PBS, without any organic solution or clean-up procedure such as SPE or liquid-liquid extraction, making it a much more simple and rapid method than previously reported ones. The detection limit in blank samples was 0.2 μg/kg. To validate this new RAC (ractopamine hydrochloride) ELISA, a RAC-free pig liver sample spiked at three different concentrations was prepared and analyzed by HPLC and ELISA. The results showed a good correlation between the data of ELISA and HPLC (R2 > 0.95), which proves that the established ELISA is accurate enough to quantify the residue of RAC in the animal derived foods.

Evaluation of a feline-specific multiplex, bead-based assay for detection of cytokines, chemokines, growth factors, and other immunologically active proteins in serum and plasma samples from cats

“…11 These effects are more common direct immunoassays, in which the antibodies and enzyme conjugate used are affected by the sample protein matrix. 12 Various strategies can be used to minimize matrix effects, including dilution. We observed a progressive increase in recovery as sample protein matrix was diluted for the CXCL-1, CXCL-8, Fas, GM-CSF, IFN-γ, IL-1β, IL-2, IL-4, IL-6, IL-13, and SCF assays, indicating a matrix effect.…”

Ractopamine as a metabolic modifier feed additive for finishing pigs: a review

“…In order to monitor the illegal use of ractopamine, it is necessary to develop proper residue detection methods in swine tissues, feeds, and urine. Recent researches have suggested instrumental methods to detect these residues (Sakai et al 2007;Shen et al 2007;Zhang et al 2009;Zhai et al 2011), but no mention of ractopamine-withdrawal period for finishing pigs were made. In this way, further studies are required to determine whether consumer safety can be assured without applying a ractopamine-withdrawal period.…”

Development of Two-Dimensional Nanomaterials Based Electrochemical Biosensors on Enhancing the Analysis of Food Toxicants

“…Further, the sensor is disposable and portable, with good reproducibility in on-site and real-time electroanalysis of the spiked pork samples. RAC is a β-adrenergic agonist, originally used to treat ailments including pulmonary disease and asthma [ 176 ]. Meanwhile, it has been illegally utilized as animal feed to reduce body fat deposition and improve protein accumulation [ 177 ].…”