Decoding genotypes is one of the most spectacular fields of research of biology. The genes in DNA contain the information that is necessary to form proteins. An established method to identify proteins without previously modifying them chemically is based on so-called nanopores. Nanopores are tiny channels in a membrane that have an incredibly small volume of approx. 10-24 m3.
The paper of researchers from Nicholas A. W. Bell's and Ulrich Keyser's team from the Cavendish Laboratory at Cambridge University entitled "Digitally encoded DNA nanostructures for multiplexed, single-molecule protein sensing with nanopores" features a groundbreaking innovation. They combined the traditional procedure with a novel detection method. For their work, these researchers were awarded the 2016 Helmholtz Prize, which was endowed with €20 000, in the category of "Precision measurements in applied metrology in the fields of physics, chemistry and medicine".
The scientists elaborated a library of customized, folded DNA molecules (DNA origami) that are able to bind exactly one protein to themselves by means of a molecular bar code. The proteins bound in this manner can then be identified with 94 % certainty with the aid of electric measurement methods. This new procedure is not only highly selective, but also allows for the first time four different proteins to be identified at the same time.
Producing nanopores for this new procedure is much easier than for traditional procedures, since nanopores can be used universally and no longer have to be adapted to each of the proteins to be identified. This new detection method works on a purely electrical basis and is therefore ideal for miniaturizing. It would be conceivable to use this new method in lab-on-a-chip systems or as portable sensors – basically as a pocket-sized method for protein analysis.