title: Chemotaxis of nonbiological colloidal rods.
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 2.0 microm 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.
authors.affiliation: Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
authors.forename: Yiying
authors.initials: Y
authors.lastname: Hong
authors.forename: Nicole M K
authors.initials: NM
authors.lastname: Blackman
authors.forename: Nathaniel D
authors.initials: ND
authors.lastname: Kopp
authors.forename: Ayusman
authors.initials: A
authors.lastname: Sen
authors.forename: Darrell
authors.initials: D
authors.lastname: Velegol
mesh_terms: D000465:Algorithms; D002633:Chemotaxis / Q000502:physiology*; D003198:Computer Simulation; D004058:Diffusion; D006046:Gold / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry*; D010984:Platinum / Q000737:chemistry*
chemical_list: D010984:Platinum; D006046:Gold; D006861:Hydrogen Peroxide