Light is being progressively used to interact with living cells. Optogenetics started in the last decade and is now used to explore brain cells and to condition them to operate in specific ways.
In an article of researchers from Oregon State University light is being used to activate a molecule absorbed specifically by cancer cells making the molecule glow and at the same time killing the cell.
The technique is different from optogenetics. Here the cell is not changed by tampering its genes to become sensitive to light. A special molecule, silicon naphthalocyanine (SiNc), is associated to a copolymer, poly(ethylene glycol)-block-poly(e-caprolactone) that is used as a vector to move around the SiNc. This molecule is readily absorbed by cancer cells and does not affect normal cells.
During surgery the surgeon illuminates the operating field with an infrared light. This causes the cells containing SiNc to glow and became visible to the surgeon. At the same time the SiNc becomes active and kills the cells hosting it.
The compound, both the SiNc and its vector, are disposed by the body with no side effects, as far as experiments conducted on mice have shown.
The first target is ovarian cancer. No date so far has been indicated for trials on humans.
Interesting to see how researchers have learnt to manipulate nanoparticles to create compounds with desired properties.