New Nanoparticle Could Provide Simple Early Diagnosis Of Many Diseases
Researchers have created a new nanoparticle that could someday act as a virtually all-purpose diagnostic tool to detect many inflammatory diseases in their earliest stages, including heart disease, Alzheimer's, and arthritis. The specially-designed nanoparticles seek out hydrogen peroxide (thought to be overproduced in trace amounts in the early stages of most diseases that involve some sort of chronic inflammation in the body), and emit light when they encounter it.
In vivo imaging of hydrogen peroxide with chemiluminescent nanoparticles Dongwon Lee, Sirajud Khaja, Juan C. Velasquez-Castano, Madhuri Dasari, Carrie Sun, John Petros, W. Robert Taylor & Niren Murthy. Published online: 19 August 2007; doi:10.1038/nmat1983
The paper describes the advantages of their nanoparticles: In the paper, they demonstrate the use of this photo-marker in live mice, and are able to image the location of hydrogen peroxide anywhere in the mouse body. An obvious question regarding the technique is the toxicity of the nanoparticles. They do not discuss this in the paper (it will probably be the subject of an upcoming study), but the particles are ester polymers, with embedded dye (a pentacene derivative). So they are not using heavy-metal nanoparticles: these are peroxalate polymers. I'm not an expert in biocompatibility, but from the chemical structure, I wouldn't expect it to be highly toxic (it probably even degrades in the body).
Obviously a detailed toxicity study would be required before use in humans. However it's possible that it could be rapidly adapted to ex-situ diagnostics (e.g. on tissue explants) and then be adapted to live in-situ imaging if/when it is determined to be safe.