A broad-specificity immunoassay was established to monitor marbofloxacin (MBF) and ofloxacin (OFX) residues in raw milk and porcine muscle samples. The main influential parameters in the assay buffer were investigated to improve the assay performance. The cross-reactivities (CRs) were lower than 0.25%, except for OFX (41.38%). The quantitative working ranges for MBF and OFX based on fortified matrices ranged from 0.11 to 30.85 ng mL⁻¹, with a 50% inhibitory concentration of 0.76±0.12 ng mL⁻¹ for MBF and 2.70±0.28 ng mL⁻¹ for OFX. The detection limits of enzyme-linked immunosorbent assay (ELISA) ranged from 0.053 to 0.358 ng mL⁻¹ in spiked samples. The mean recoveries were in the range of 80.52–95.46%, less than 12.06% of the coefficient of variation. A good correlation between the ELISA results and those from instrument methods demonstrated the practical application of the novel ELISA. Therefore, the immunoassay proposed is feasible for MBF and OFX analysis in animal-derived foods.

With the increasingly serious problem of aminoglycoside antibiotic residues, it is imperative to develop rapid, sensitive and efficient detection methods. This article reviews the detection methods of aminoglycoside antibiotics in animal-derived foods, including enzyme-linked immunosorbent assay, fluorescent immunoassay, chemical immunoassay, affinity sensing assay, lateral flow immunochromatography and molecular imprinted immunoassay. After evaluating the performance of these methods, the advantages and disadvantages were analyzed and compared. Furthermore, development prospects and research trends were proposed and summarized. This review can serve as a basis for further research and provide helpful references and new insights for the analysis of aminoglycoside residues. Accordingly, the in-depth investigation and analysis will certainly make great contributions to food safety, public hygiene and human health.

A new molecularly imprinted polymer (MIP)-chemiluminescence (CL) method has been developed for the detection of ethopabate (ETP) residues in chicken muscle. The MIP microspheres were prepared using precipitation polymerization with ETP as a template, methacrylic acid as a functional monomer and pentaerythritol triacrylate as a cross-linker in the porogen of acetonitrile. The prepared MIP microspheres were characterized by using a scanning electron microscope, differential scanning calorimeter and Fourier transform infrared spectrometer. The binding properties of ETP on the imprinted polymers were evaluated by the equilibrium rebinding experiment. It was revealed that two classes of binding sites were produced in the resulting ETP MIPs with the dissociation constants of 23.92 μg L⁻¹ and 77.82 μg L⁻¹, and the affinity binding sites of 8808.28 μg g⁻¹ and 14 043.90 μg g⁻¹, respectively. As the artificial biomimetic recognition element for ETP, the polymer microspheres were immobilized in microtiter plates (96 wells) with poly(vinyl alcohol) as a glue. Through the optimization of the MIP absorption and CL imaging conditions, ETP was quantified based on the peroxyoxalate CL reaction enhanced by imidazole. Under the optimum conditions, the relative CL intensity has a linear relationship with the ETP concentration in the range of 0.1 μg mL⁻¹ to 30 μg mL⁻¹, with a limit of detection of 14.7 μg kg⁻¹ and a limit of qualification of 20.4 μg kg⁻¹ in chicken muscle. The recoveries of spiked ETP are in the range of 99.80% to 99.98% with a relative standard deviation of 1.7% to 3.4%. For the first time, the CL method combined with MIPs was developed to determine trace ETP in real samples, and the results show that it can become a useful analytical tool for quick detection in residue analysis.