Nature Nanotechnology publishes nanocrystal upconversion breakthrough
In collaboration with Macquarie and Peking universities IPAS researchers have found a way to make upconverting nano crystals 70% brighter, paving the way for improvements in applications from biosensing to security inks and with potential to remove barriers which currently limit the sensitivity of sensors.
Upconverting nanocrystals are really useful but until now their brightness has been seriously limited by internal quenching that occurs at rather low concentrations of activator ions within the crystals. The authors found that by hitting the nanocrystals with a much more powerful beam of light the concentration of those activator ions in the nanocrystals can be increased up to sixteen times before the brightness of the upconverted emission began to tail off. These nanocrystals were so bright that the ability to track a single crystal as in solution as it was drawn into a dip sensor made from a Microstructured Optical Fibre was reported in the paper “Single-nanocrystal sensitivity achieved by enhanced upconversion luminescence“.
Potential applications for brighter upconverting nanocrystals explored in the paper:
- sensing platforms for clinical point of care, chemical & biological applications
- immunofluorescence imaging
- rare event cell detection & quantification
- document security & security printing.
Work has already begun to see if discoveries reported in this paper can be used to overcome some limits to the sensitivity of sensors which exploit novel architectures developed by IPAS. More sensitive sensors based on tiny probes that allow real-time, in-situ detection will allow scientists to ask and answer some very profound questions indeed. Stay tuned…