University of Rochester researchers have patented a simple device just a few millimeters across that can separate microscopic objects such as DNA or cells in a fraction of a second –thousands of times faster than conventional methods.

They induce an electrical field around the droplet to be analyzed, and in one-tenth of a second the droplet elongates along an electrode into an electrified, liquid string. As the fluid is stretched, the electrical field separates the molecules laterally along the edges of the long droplet. Stretching the droplet along a specially prepared detector can lay down one set of molecules directly onto the detector, making their recognition highly efficient.

The most common method of separating proteins, called gel electrophoresis, requires more liquid and can take several hours.