Abstract: The objective of this study was to establish a quantum dot-based fluorescence immunochromatographic assay for the rapid simultaneous detection of lead and cadmium. Mouse anti-Cd2+-IEDTA and anti-Pb2+-IEDTA monoclonal antibodies were separately coupled with CdSe/CdS core-shell quantum dots embedded in polystyrene microspheres. The optimum reaction time of the dual test strip was 5 min. Pb2+ concentrations of 1–500 ng/mL, and Cd2+ concentrations of 1–400 ng/mL were detectable using the proposed method with coefficients of variation of less than 10%. Moreover, there was no cross-reactivity with other metal ions. The results of this assay were correlated well with those of inductively coupled plasma-mass spectrometry (ICP-MS) for commercial meat samples. This dual fluorescence immunochromatographic assay provided an applicable method for the rapid and simultaneous quantitative detection of lead and cadmium in meat.

Key words: cadmium, lead, monoclonal antibody, quantum dots, dual assay