A prototype of a rationally designed chemically powered Brownian motor

The design and development of a molecular system functioning as a prototype of a Brownian motor is presented. The road towards the molecular motor is illustrated with previous attempts preparing other mechanical devices, such as a molecular brake and a molecular ratchet. Thermal and chemical energy are used to achieve unidirectional rotation in the Brownian motor. The similarities of synthetic molecular devices with biological – microscopic – and mechanical – macroscopic – systems and the perils of extrapolating macroscopic principles to the molecular level are also discussed. Received: 15 November 2001 / Accepted: 14 January 2002 / Published online: 22 April 2002