Determination of Marbofloxacin Residues in Beef and Pork with an Enzyme-Linked Immunosorbent Assay

• Published in: Journal of agricultural and food chemistry Vol. 57; no. 13; pp. 5971 - 5975
• Main Authors: Sheng, Wei, Xia, Xunfeng, Wei, Keyi, Li, Ji, Li, Qing X, Xu, Ting
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 08-07-2009
• Subjects: animal tissue extracts; Animals; Anti-Bacterial Agents - analysis; antibiotic residues; antibiotics; beef; beef cattle; Biological and medical sciences; Cattle; chemical concentration; chemical structure; cross reaction; detection; detection limit; Enzyme-Linked Immunosorbent Assay; Female; fluoroquinolone antibiotics; Fluoroquinolones - analysis; food animals; Food Chemistry/Biochemistry; food contamination; Food industries; Fundamental and applied biological sciences. Psychology; General aspects; Hygiene and safety; inhibitory concentration 50; liquid chromatography; marbofloxacin; mass spectrometry; Meat - analysis; Meat and meat product industries; Muscles - chemistry; pork; quantitative analysis; Rabbits; Sensitivity and Specificity; Swine; validity; food safety; food contamination; Marbofloxacin; beef; pork; antibiotics; ELISA; Meat product; Enzyme immunoassay; Contamination; Assay; Antibiotic; Residue; Food safety; Beef; Detection; Marbofloxecln; ELISA assay; Pork; Food
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/jf900940n

Marbofloxacin is a fluoroquinolone veterinary antibiotic. An indirect competitive enzyme-linked immunosorbent assay (ELISA) was developed for the detection of marbofloxacin using polyclonal antibody. The half-maximum inhibition concentrations (IC50) and limit of detection (LOD, calculated as IC20) of the ELISA for marbofloxacin in phosphate buffer were 4.6 and 0.6 ng/mL, respectively. The assay showed little cross-reactivity with marbofloxacin structural analogues, except for ofloxacin (148%). Matrixes from the extracts of beef and pork muscle have shown a significant influence on the ELISA. Standard curves of ELISA for marbofloxacin in the extracts of the appropriate marbofloxacin-free control muscles were used in the analysis of marbofloxacin in the animal muscles without any cleanup. The average recoveries of intra- and interassay for marbofloxacin from fortified muscle samples, at five concentrations of 10, 50, 100, 500, and 1000 ng/g, were 87−93 and 84−95%, respectively. The LOD of this assay for marbofloxacin in real muscle extracts was 0.8 ng/mL. A survey of 55 animal muscle samples purchased from local markets by the ELISA was conducted, and marbofloxacin was detected in one of them at a concentration of 22 ng/g. This positive sample was validated by liquid chromatography−electrospray ionization−tandem mass spectrometry (LC−ESI−MS/MS) to be 28 ng/g of marbofloxacin.