How To Trap DNA molecules With Your Smartphone

Researchers from the University of Minnesota College of Science and Engineering have found yet another remarkable use for the wonder material graphenetiny electronictweezers” that can grab biomolecules floating in water with incredible efficiency. This capability could lead to a revolutionary handheld disease diagnostic system that could be run on a smart phoneGraphene, a material made of a single layer of carbon atoms, was discovered more than a decade ago and has enthralled researchers with its range of amazing properties that have found uses in many new applications from microelectronics to solar cells. The graphene tweezers developed at the University of Minnesota are vastly more effective at trapping particles compared to other techniques used in the past due to the fact that graphene is a single atom thick, less than 1 billionth of a meter.

The physical principle of tweezing or trapping nanometer-scale objects, known as dielectrophoresis, has been known for a long time and is typically practiced by using a pair of metal electrodes. From the viewpoint of grabbing molecules, however, metal electrodes are very blunt. They simply lack the “sharpness” to pick up and control nanometer-scale objects.

Graphene is the thinnest material ever discovered, and it is this property that allows us to make these tweezers so efficient. No other material can come close,” said research team leader Sang-Hyun Oh, a Professor at the University of Minnesota. “To build efficient electronic tweezers to grab biomolecules, basically we need to create miniaturized lightning rods and concentrate huge amount of electrical flux on the sharp tip. The edges of graphene are the sharpest lightning rods.

The team also showed that the graphene tweezers could be used for a wide range of physical and biological applications by trapping semiconductor nanocrystals, nanodiamond particles, and even DNA molecules. Normally this type of trapping would require high voltages, restricting it to a laboratory environment, but graphene tweezers can trap small DNA molecules at around 1 Volt, meaning that this could work on portable devices such as mobile phones.

The research study has been published  in Nature Communications.