Highly biocompatible POSS-coated CdTe quantum dots for cell labeling

The CdTe QDs coated by octa-mercaptopropyl polyhedral oligomeric silsesquioxane (OM-POSS) were successfully applied in cell labeling as a fluorescent probe. SiHa cells and mouse preosteoblast cells MC3T3-E1 were employed to evaluate the cell toxicity of the POSS-CdTe QDs and CdTe QDs. The cells incubated with POSS-CdTe QDs show higher viability than those with CdTe QDs under the same conditions. More POSS-CdTe QDs are internalized into cells via endocytosis than CdTe QDs during the same incubation time, which is vividly exhibited in laser confocal images. The highly biocompatible CdTe QDs with amphiphilic OM-POSS coating allow rapid intracellular uptake, enabling the use of lower concentrations of QDs for an overall reduced toxicity. The as-prepared POSS-CdTe QDs have enormous potential for long-term live cell and in vivo imaging applications.