A team of researchers from Delft University of Technology announces a new type of nanopore devices that may significantly impact the way we screen DNA molecules, for example to read off their sequence. In a paper entitled 'DNA Translocation through Graphene Nanopores' (published online in Nano Letters), they report a novel technique to fabricate tiny holes in a layer of graphene (a carbon layer with a thickness of only 1 atom) and they managed to detect the motion of individual DNA molecules that travel through such a hole.
There is a worldwide race to develop fast and low-cost strategies to sequence DNA, that is, to read off the content of our genome. Particularly promising for the next generation of sequencing are devices where one measures on single molecules. Imagine a single DNA molecule from one of your cells (3 billion bases, 1 meter long if you would stretch it from head to tail) that is read base per base in real time while sliding between two of your fingers. This is what postdoc dr. Gregory Schneider in the group of professor Cees Dekker and colleagues from the Kavli Institute of Nanoscience have in mind. They now demonstrated a first step in that direction: To slide a single molecule of DNA through a tiny nanoscale hole made in the thinnest membrane that nature can offer, a 1-atom thin layer of graphene.
Graphene is a unique and very special material, and yet widely available: Everyone has graphene at home: graphite is made of layers of graphene and occurs in for example the carbon of pencils, charcoal, or candle soot. But in this research, graphene is used because of that special property that one can make single-atom-thin monolayers of graphene. Why is such an ultrathin membrane important? Let's go back to that wire sliding between your fingers. The distance between two bases in DNA is very small, about half a nanometer, which is 100000 times smaller than the width of a human hair! To read off each base along the DNA, o
|Contact: Prof. Cees Dekker|
Delft University of Technology