Exciting technology: light fantastic
New developments in digital display are down to nanotechnology
Just a few thousands of atoms each, quantum dots are being used as tiny beacons or markers that can be used to watch and track cells, genes, proteins and other small molecules. When a beam of light is shone upon a quantum dot, the electrons in its core become excited and re-emit light – at a wavelength that depends on the size of the core. By altering the size of the core, researchers can ﬁne-tune quantum dots to emit light at a variety of wavelengths, producing a set of multicoloured markers.
The dots can be a thousand times brighter and last much longer than conventional dyes. In one study, scientists used quantum dots to watch blood ﬂow in the tissues of living mice. The images were so detailed they showed blood vessel walls rippling with each heartbeat.
Adding antibodies or other molecules to the dots can be used to target them very speciﬁcally. Whole cells can be labelled and tracked – more than 100 different cells simultaneously. Proteins on the surface of cells, such as cancer cells, can be identiﬁed. Even the movements of individual proteins can be followed inside a cell.
Companies are already selling quantum dot-based products for use in the lab. Quantum dots are also being used for digital display. In 2013, Amazon’s Kindle Fire HDX became the first product on the market using quantum dot display. It’s likely that more and more products using quantum dot display technology will become available over the coming years.Lead image:
Argonne National Laboratory/Flickr CC BY NC