Posted on Apr 01, 2014, 6 a.m.
Custom-designed nanoparticles carry chemotherapy drugs directly to tumor cells and release their cargo when triggered by laser.
Light-activated drug delivery holds promise for treating cancer because it give doctors control over precisely when and where in the body drugs are released. Delivering and releasing chemotherapy drugs so that they hit only tumor cells and not surrounding healthy tissues can greatly reduce treatment side effects and increase the drugs' cancer-killing effect. But the development of a drug-delivery system that responds to tissue-penetrating light has been a major challenge. Jeffrey Zink, from the University of California/Los Angeles (UCLA; California, USA), and colleagues have developed an innovative cancer-fighting technique in which custom-designed nanoparticles carry chemotherapy drugs directly to tumor cells and release their cargo when triggered by a two-photon laser in the infrared red wavelength. The researchers innovated a new type of nanoparticle equipped with thousands of pores, or tiny tubes, that can hold chemotherapy drugs. The ends of the pores are capped with nanovalves that keep the drugs in, like a cork in a bottle. The nanovalves contain special molecules that respond to energy from two-photon light exposure, which prompts the valves to open and release the drugs.
Jonas Croissant, Arnaud Chaix, Olivier Mongin, Fuyuhiko Tamanoi, Daniel P. Ferris, Derrick Tarn, Jeffrey I. Zink, et al. “Two-Photon-Triggered Drug Delivery via Fluorescent Nanovalves.” Small, 20 Feb. 2014.