Scientists from UCLA's California NanoSystems Institute and Korea's Yonsei University have developed an innovative method that enables nanomachines to release drugs inside living cancer cells when activated remotely by an oscillating magnetic field. In recent years, cancer research has increasingly focused on developing therapies that, unlike chemotherapy, target only cancer cells while leaving healthy cells unharmed. To that end, scientists have created nanomachines that can trap and release drug molecules from pores directly into individual cancer cells in response to an external and noninvasive method of activation for the most effective results. The new method uses a material that combines a framework of mesoporous silica nanoparticles with magnetic zinc-doped iron oxide nanocrystals, along with attached nanovalves that help hold drug molecules in the pores. When an oscillating magnetic-field stimulus is applied, it causes the zinc-doped iron oxide nanocrystals to heat. This increased heat causes the molecular machines to activate, and the valves to open and release the drug molecules (doxorubicin) from the pores into the target cells. The hydrophobic nature of the interior of the pores, as well as the ability to functionalize the silica surface with hydrophilic functionalities, makes these particles attractive for anti-cancer drug delivery. Adding a magnetic core to the silica-based nanoparticles is of interest for its potential applications in magnetic resonance imaging. Thus the ultimate goal would be to develop this system to have applicability in treatment of cancer patients.