Abstract
Chemotaxis is the movement of organisms toward or away from a chemical attractant or toxin by a biased random walk process. Here we describe the first experimental example of chemotaxis outside biological systems. Platinum-gold rods long exhibit directed movement toward higher hydrogen peroxide concentrations through “active diffusion.” Brownian dynamics simulations reveal that no “temporal sensing” algorithm, commonly attributed to bacteria, is necessary; rather, the observed chemotaxis can be explained by random walk physics in a gradient of the active diffusion coefficient.
- Received 21 June 2007
DOI:https://doi.org/10.1103/PhysRevLett.99.178103
©2007 American Physical Society