Inventing a useful new tool for creating chemical reactions between single molecules, scientists at the National Institute of Standards and Technology (NIST) have employed microfluidics-the manipulation of fluids at the microscopic scale-to make microdroplets that contain single molecules of interest. By combining this new microfluidic "droplet-on-demand" method with "optical tweezers" that could merge multiple droplets and cause their molecular contents to react, the research may ultimately lead to a compact, integrated setup for obtaining single-molecule information on the structure and function of important organic materials, such as proteins, enzymes, and DNA.
Physicists Carlos López-Mariscal and Kristian Helmerson created a tiny microfluidic device with a Phannel through which water can flow. In the microfluidic channel, the water is laced with desired molecules of just the right concentration, so that resulting droplets each pick up on average just one molecule of interest.
López-Mariscal is a member of SPIE, and an author of a paper presented on the topic at SPIE Optics and Photonics in August.
Full press release from NIST
SPIE Digital Library paper: Optical trapping of hydrosomes (open access)