Creating a Chemical Gradient in a Microfluidic Device

The image I have submitted is a photograph of the microfliuidic device I have designed and fabricated with colored dye in it. The device picture will be used to induce a directionally changing chemical gradient. This gradient subsequently induces a change in the cells that will be trapped in the diamond shaped area. Microfluidic devices are used to exploit the unique features of the sub-millimeter scale. In this case, the channels with colored dye are only 150 microns (1x10-6m) wide and 15 microns tall. This means that there is no mixing of fluids unless a device is purposely designed otherwise, as in the case of the device pictured. We use colored dye as visual documentation in this device because it is a good way to determine if there is a gradient manufactured in the diamond shaped cell trapping area. The picture here is of one of four mixers attached to the cell trapping area. I have used two different colored dyes to show that a gradient has been created. This is important because when we use chemicals to induce changes in the cells we will not be able to visualize the gradient so we need to know what conditions will get our desired results before we start our experiments.