Will Improved Quantum Dots Spur Use for Biological Analysis?

IN Discussion Topics, Uncategorized

In the 1980s, Quantum Dots were highly promoted as the solution to single molecule detection for biological analysis. These nanocrystals have several advantages over organic dyes:   they are much brighter, and they are highly stable, so do not saturate or “bleach” with increasing excitation light intensity. Quantum Dots  have a relatively broad excitation curve (several hundreds of nanometers) but narrow emission curves, thus  facilitating multiplexed analysis beyond two colors.  The initial promise of Quantum Dots for biological applications has not been fully realized due to their tendancy to ‘blink’ off and on, which can limit their utility for rapid biological reactions and single molecule detection, and the variable size for different colors can contribute to steric hindrance for enzymatic reactions such as DNA polymerase. However, a recent article cites a group at MIT (Chen, et al.) that has developed a new method for manufacturing Quantum Dots that enhances their performance in several ways: eliminates the blinking, results in consistent size and brighter emission, and narrows the emission spectra even further. The question now is when these enhanced Quantum Dots become commercially available, will they gain more widespread application for biologists?