Optimized immonochromatographic system for antigen determination based on monoclonal antibody conjugates with quantum dots

Optimized immonochromatographic system for the determination of antigens of viruses based on conjugates of monoclonal antibodies with multilayer colloidal quantum dots (QDs) as fluorescent labels was developed. The main attention was paid to the choice of the structure and synthesis of stable QDs with optimal spectral properties for analysis, to the selection of the conditions of synthesis of antibody conjugates with QDs, to the production of test strips for immunochromatographic analysis, and to the development of fluorescent reader design. It is shown that the optimal region of QDs fluorescence lies in near infrared range (700 – 800 nm). The stable QDs CdTeSe/CdS/CdZnS/ZnS and their conjugates with monoclonal antibodies for detecting Aujeszky's disease virus were synthesized, which fluorescent in this spectral region. Using these QDs, limit of detection of antigen equal to 30 pM was obtained.