Monoclonal antibody production based on different chelators and development of time-resolved fluorescent microsphere lateral flow immunoassays for lead detection.

Abstract

Lead contamination in agricultural products and foods is increasing, which has impacted on human health. To effectively detect lead residues in foods, time-resolved fluorescent microspheres lateral flow immunoassays (TRFMs-LFIAs) were developed utilizing two antibodies produced based on two chelators. The qLOD (quantitative limit of detection) of two TRFMs-LFIAs were 0.24 ng/mL and 0.09 ng/mL, respectively. Their vLOD (visual limit of detection) were 20 ng/mL and 10 ng/mL, respectively. They showed no significant cross-reactivity with 12 tested metal ions. The TRFMs-LFIAs demonstrated strong concordance with graphite furnace atomic absorption spectrometry (GFAAS) in detecting Pb2+ in real samples. They could meet the specific and rapid detection needs for Pb2+ in the field. Furthermore, the main interaction forces and key amino acids involved in the interaction between antibodies and lead-chelator complexes were investigated using molecular docking. This study contributed to the development and understanding of heavy metal immunoassays.