Smart Drugs Get Zapped

A gel that can be injected under the skin releases drugs when stimulated by a weak electric field applied from outside the body (ACS Nano, DOI: 10.1021/nn203430m). The new material, designed by Stanford University’s Richard N. Zare and colleagues, is based on conductive-polymer nanoparticles loaded with drugs. When exposed to a weak electric field, which can easily be generated by a AA battery, the charge on the polymer changes, causing the material to release the drugs. Zare and his team hold the particles in place by suspending them in a temperature-sensitive material that is liquid at room temperature and turns into a gel at body temperature. Preliminary tests showed that they could control the dosage and timing of the drug release by varying the strength and duration of the applied field. They also injected nanoparticles loaded with a fluorescent dye under the skin of mice and watched the dye spread through the animals’ sides after a short electrical pulse. The Stanford group is now studying controlled drug dosages in animals with support from the drug company Sanofi.