Rapid Determination of Cephalexin in Animal-Derived Food by an Indirect Competitive Enzyme-Linked Immunosorbent Assay

Abstract

Cephalexin (CFE) residues in animal-derived food and its deleterious effects on human health has attracted extensive attention. In this study, a specific anti-cephalexin monoclonal antibody (mAb) was used to develop an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) with a half-maximal inhibitory concentration (IC₅₀) of 1.83 µg/L that was suitable for the determination of cephalexin in animal-derived foods. The limit of detection (LOD) and limit of quantitation (LOQ) for cephalexin were from 0.44 to 0.58 µg/kg and 0.57 to 0.67 µg/kg, respectively. The recovery was from 90.1 to 103.6% with coefficients of variation (CV) less than 10.0%. In addition, the established ELISA method and high-performance liquid chromatography – mass spectrometry (HPLC-MS/MS) were used to analyze the samples with good correlation between the results. The results show that the established ic-ELISA is suitable for the determination of cephalexin in animal-derived food.

Keywords:

• Animal-derived food
• cephalexin
• high-performance liquid chromatography-mass spectrometry
• indirect competitive enzyme-linked immunosorbent assay
• monoclonal antibody

Data availability statement

The data presented in this study are available on request from the corresponding author.

Additional information

Funding

The work was financially supported by the Key Research and Development Programof Hubei Province (CN) (2020BBB079).