Synthesis of magnetic and fluorescent bifunctional nanocomposites and their applications in detection of lung cancer cells in humans

We developed a novel strategy to detect lung cancer cells by utilizing magnetic and fluorescent bifunctional nanocomposites (BNPs) in combination with monoclonal anti-carcinoembryonic antigen (CEA) antibodies. The BNPs, consisting of silica-coated superparamagnetic nanoparticles and quantum dots (QDs), exhibited high luminescence and were easily separated in an external magnetic field. The binding specificity of the antibody-conjugated BNPs (immunonanoparticles) were confirmed via incubating with human lung adenocarcinoma SPCA-1 cells, human leukemic K562 cells and human embryonic lung fibroblasts MRC-5 cells. Further experiments demonstrated that the as-prepared immunonanoparticles can efficiently capture and detect cancer cells in pleural effusion from lung cancer patients. These results suggest that this method, of which the detection procedures are completed within 1 h, could be applied to the rapid and cost-effective monitoring of cancer cells in clinical samples.