A Touchable Molecular Communication Model of Targeted Contrast Agent Delivery

We propose a potential architecture of a microrobotic platform for transporting contrast agent inside the body in contrast-enhanced medical imaging (CMI), and analyze the targeting performance using a "touchable" molecular communication model. The remote controllability and trackability of microbots lead to such a "touch-communication" (TouchCom) mode. These microbots (i.e., message carriers in the context of molecular communications) are responsible for the delivery of contrast agent nanoparticles (i.e., message). The loading/injection and unloading of the contrast agent correspond to the transmitting and receiving processes, respectively. Subsequently, we define the propagation delay, path loss, as well as angular and delay spectra of targeting intensity, which are parallel to their counterpart concepts in the conventional wireless channel and are important parameters from the perspectives of both targeting and communication. We also present simulation tools for the propagation and transient characteristics of microbots in the blood vessels.