A method of indicating the location nanoparticles in the body of a mammal, which method comprises the steps of: (a) stimulating nanoparticles within a part of the body to produce heat so that there is a temperature differential in said part； and (b) imaging the part using electrical impedance tomography, the location of nanoparticles indicated by one or more region within said part having a greater temperature than other regions of said part.
