Chemotherapy is an effective therapy for cancer, except for the side effect of killing the rest of the body with the toxin. Being able to deliver chemo drugs directly to the tumor while sparing the body’s healthy tissues may allow higher doses of the drug to attack cancer without killing the patient. Researchers at UCLA and University of Montpellier in France have developed light-activated particles that release their payloads when a special laser shines illuminates them.
The technique is based on mesoporous silica nanoparticles (MSN) the pores of which are filled with a chemo drug and plugged by “pseudo-rotaxane constituted by an azobenzene stalk and a β-cyclodextrin moiety.” When a two-photon laser illuminates the nanoparticles, the pores unclog and the medication is released. Because the laser frequency is set in the infrared range, the light penetrates sufficiently into the body to reach targets within about 1.5 inches (4 cm), allowing for a variety of tumors, such as of the skin and breast, to receive treatment.
Besides opening up pores of the nanoparticles to release the drugs inside, the same laser can be used to fluoresce the particles and visualize whether they reach their target.
Study in journal Small: Two-Photon-Triggered Drug Delivery via Fluorescent Nanovalves…
UCLA: Let there be tissue-penetrating light: Scientists develop new nanoscale method to fight cancer…