Nanorice is made of non-conducting iron oxide called hematite that's covered with gold. The core size and shell thickness vary slightly but the particles are about 20 times smaller than a red blood cell. Nanoparticle's shape could improve chemical sensing, biological imaging. Nanoparticles like nanorice can be used to focus light on small regions of space. In form, nanorice is similar to nanoshells, a spherical nanoparticle Halas invented in 1998 that is currently being examined for possible applications in molecular imaging, cancer treatment, medical diagnostics and chemical sensing. Both nanorice and nanoshells are made of a non-conducting core that is covered by a metallic shell.
Halas' investigations find that nanorice possesses far greater structural tunability than nanoshells and another commonly studied optical nanoparticle, the nanorod. In fact, tests indicate that nanorice is the most sensitive surface plasmon resonance (SPR) nanosensor yet devised. The nanorice core is made of non-conducting iron oxide and the outer covering of gold. The nanorice particles described in the Nano Letters paper were about 360 nanometers long and about 80 nanometers in diameter.