An injectible compound that glows in different colors depending on the amount of intracellular oxygen is discovered by researchers.
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The material consists of europium, which glows red, and terbium lanthanide emits a green glow. Europium’s light emission is not affected by the presence of oxygen, but at lower oxygen levels terbium’s green color gets brighter.
Though nanoparticles have been designed in a similar pattern, one could never tell whether the colour change is due to an abnormal level of oxygen or simply too many of the particles concentrating in one area.
Focusing on the colour of the emitted light rather than its intensity by the new rare earth nanoparticles solves the problem of distinguishing the emission. The investigators believe that the technology will be tested in human subjects as they have progressed quite a bit in the laboratory already.
Source-Medindia