Quantum Dots Pose Minimal Risk To Cells in Tests Conducted By Federal Lab
NWN Hears from Lead Scientist, Dr. Fanqing Frank Chen, About These Promising Results.Using an advanced toxicogenomics tool to study quantum dots, Fanqing Frank Chen, PhD, a scientist at Lawrence Berkeley National Laboratory and his team (including first author Tingting Zhang) reported that quantum dots pose little impact to cells.
Schematics of the PEG-silica embedded qdots. The silica shell is functionalized with –SH groups and with PEG group. The latter provide additional stability and reduced non-specific bindings. The scale bar (~3 nm) provides a qualitative comparison between the overall size of the silanized dot (~8nm) and the size of the semiconductor core (~3nm).
Qdots localization in HSF42 cells, after 48 hrs of incubation. The nuclei are stained with DAPI, a blue dye. Yellow qdots are localized either in the cytoplasm or in the perinuclear region. Notice that about half of the cells in the image are in the post-mitotic stage.
Courtesy of Dr. Fanqing Frank Chen, Lawrence Berkeley National Lab
These findings provide further evidence that quantum dots that enter a cell can provide many benefits, such as researching the inside of cells and identifying cancer cells to deliver treatment. Dr. Chen tells NWN, “The coating chemistry allows the quantum dots to be used for almost all in vitro biological applications. The whole genome analysis paves way for in vivo application of quantum dots.”
Advancements in nanoscale technologies have helped Dr. Chen and his colleagues uncover these exciting findings about quantum dots and their reaction within cells. “The main advancements came from the surface chemistry modification chemistry developed in Dr. Paul Alivisatos' group at the University of California, Berkeley,” notes Dr. Chen. “This chemistry provided real robust and stable coating for quantum dots, in addition, the coating helped to make the nanoparticle water soluble, opening the door for multiplex of biological applications.”
According to Dr. Chen, the next steps in the evaluation of the quantum dots toxicity will be in vivo studies with animal models, long-term pharmacotoxicity studies, mutagenesis studies, and pharmacokinetic studies.