At John Hopkins, researchers have developed a nanoparticle as a new biosensor to treat damaged retinal cells.
Biosensor detects oxidative stress inside the cells. It responds by regulating therapeutic gene expression. This reduces the damage caused by the free radicals.
Biosensor has an outer lipid layer. This layer also has some targeting proteins. These proteins recognize the endothelial cells lining the eye's blood vessels. The lipid outer layer ensures easy entry of the biosensor into the cell.
Once inside the cells, the DNA is exposed. If there is oxidative stress, the promoters are activated and two proteins are expressed. One, a fluorescent protein that helps in detection of the damaged cells; two, a therapeutic protein that reduces the damage.
They have tested the biosensor in animal models like mouse, rabbits, and dogs. These nanoparticles were also found to be nontoxic on cells but animals showed varied levels of toxicity.
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