Ferritin-Based Single-Electron Bio-Nano Devices

In this work, we study, for the first time, the electrical response of single-ferritin particles at low temperatures. Our approach, based on wide (10 um) and small (8-25 nm) self-aligned-nano-gaps devices, facilitates the trapping of single ferritin particles. Below 100 K, the devices are stable enough to allow the acquisition of reproducible currents vs. voltage characteristics. A striking feature of single ferritin particles is that the data is in excellent agreement with the Coulomb blockade model, revealing single-electron tunneling as the main transport mechanism through them.<br/>A ferritin single-electron device is, on one hand, a system for studying the electron transport phenomena in ferritin, and therefore it broadens the scarce present knowledge on single ferritin particles: as such single-electron devices could reveal information about ferritin that may be of importance in understanding its role in neurodegenerative diseases. On the other hand, it is a basic tool for future bio-based electronics, in particular, for the fabrication of protein-based single-electron transistors, due to the exceptional stability of the devices and reproducibility of the current vs. voltage characteristics.