Here’s a chance to see some of the microfluidic systems I’ve developed in action. Many of my research projects have involved fluorescence microscopy of dynamic transport processes on micro- and nanofluidic devices. As a result, my data sometimes include videos of these processes occurring.
Controlling Sample Tranport
This video shows how a sample stream of fluorescent peptide loads from the sample channel on the chemical cytometry device into the separation channel. Over the course of the video, the electric field strength in the separation channel increases, improving the sample stream loading. Read more about sample loading in this device.
Watching Bacterial Swimming
Caulobacter crescentus bacteria change their swimming behavior in the presence of a xylose gradient at the intersection of this device. This response is called chemotaxis and allows cells to respond to their environments, for example, to travel toward a carbon source. The xylose is loaded into a lower, horizontal channel, which intersects the cell channel near the center of the region shown in the video. At this intersection, the xylose diffuses across a nanoporous membrane into the upper, vertical channel to affect the cells. Read more about Caulobacter chemotaxis on this device.
Trapping Cells
This video shows Caulobacter crescentus bacteria being trapped at the tips of conical nanopores by electrokinetic forces. A nanoporous membrane is sandwiched between two perpendicular microchannels, one of which contains the bacteria to be trapped. The bacteria express a fluorescent protein so they show up bright against the dark background. Read more about electrokinetic trapping in this device.