"Smart" microcapsules will cure cancer and repair plastic

Researchers at the University of California at Berkeley have developed microcapsules that are destroyed by light rays, releasing their contents. This unique property can have wide practical applications, including cancer chemotherapy.

Light rays are easy to focus and direct to the desired point, thus destroying cancer cells or affecting larger areas.

The new microcapsules are spherical nylon particles the size of a grain of sand. Inside they contain a liquid substance, and on top they are dotted with carbon nanotubes. Nanotubes convert laser radiation into heat, which causes the nylon capsule to rupture, releasing the substance from it. With such technology, doctors can, for example, inject microcapsules with an anti-cancer drug and, by locally acting with a laser on a cancerous tumor, ensure the destruction of capsules and the release of their contents exactly where required.

In addition to the possibility of selective delivery of chemotherapy drugs to diseased tissues, such microcapsules can be used to create self-healing plastics, Jean Fréchet and colleagues note in their article "Chemicals On Demand with Phototriggerable Microcapsules" in the weekly issue of the Journal of the American Chemical Society. Scientists suggest adding two types of microcapsules to polymers: one filled with a monomer, the other with a catalyst. As a result of the damage, the capsules are torn, their contents leak out, polymerize and seal the crack.

Portal "Eternal youth" http://vechnayamolodost.ru based on EurekAlert: Next-generation microcapsules deliver 'chemicals on demand'02.11.2009