| 20090311737 | METHOD AND DEVICE FOR GENERATING DIFFUSIVE GRADIENTS IN A MICROFLUIDIC CHAMBER - A microfluidic device is described, capable of generating multiple spatial chemical gradients simultaneously inside a microfluidic chamber. The chemical gradients are generated by diffusion, without convection, and can either be maintained constant over long time periods, or modified dynamically. A representative device is described with a circular chamber in which diffusion occurs, with three access ports for the delivery and removal of solutes. A gradient typically forms in minutes, and can be maintained constant indefinitely. Gradients overlapping with different spatial location, and a controlled rotation of a gradient formed by diffusion are demonstrated. The device can also be used to evaluate chemotactic responses of bacteria or other microorganisms in the absence of convective flow. | 12-17-2009 |
