Blue jean dye kills cancer cells.

The common dye found in blue jeans and ballpoint pens is called phthalocyanine and is a light-activated, or photosensitive, agent with cell-destroying properties. But it is not water soluble and so don't take off those pants just yet, you're safe. So how do you kill cancer cells with it? Well using gold nano particles coated with the dye as a trojan horse for delivery and then shinning a laser at the right spot to activate the dye. Seems to work in HeLa cells anyways. Bonus: I got to use laser, nanoparticle, and blue jeans in the same paragraph...