Preparation of anti-melamine antibody and development of an indirect chemiluminescent competitive ELISA for melamine detection in milk

An indirect chemiluminescent competitive ELISA (CL-ELISA) method was developed to detect residues of melamine in milk. A high-quality polyclonal antibody towards melamine cyanurate (MC) was prepared based on synthesis of a novel immunogen. The method is applicable over the range of 0.5–7.0 µg.mL⁻¹ of MC, with an IC₅₀ value of 1.7 µg.mL⁻¹. The developed method was used in the detection of melamine residue in milk with the detection limit of 1 ng.mL⁻¹. There was no cross-reactivity with commonly used veterinary drugs. The CL-ELISA method developed provides an alternative to chromatography spectrometry for regulatory analysis of melamine in milk and could be promisingly used to improve the sensitivity of the available ELISA test kits.