Functionalized Quantum Dot Characterization and Applications in Neurosciences

Antibody or peptide conjugated nanoparticles are a new technology useful for targeting and imaging biological systems. However, characterization of these functionalized nanoparticles has not yet been accomplished. This is essential for the evaluation of the efficacy of the nanoparticles. In this study, we characterize antibody functionalized quantum dot nanocrystals from experimental data. We found that the number of functionalized antibodies bound to quantum dots varied significantly for different conjugation methods (direct antibody conjugation to the surface of quantum dots versus biotinylated antibody conjugated to streptavidin coated quantum dots) and are much lower than previously reported estimates[1]. These results explain difficulties labeling neurons and glial cells using direct antibody bound nanocrystals[2] and highlight the importance of characterizing nanoparticles before evaluating and interpreting biological data.