Scientists at the Braunschweig University of Technology have developed tiny adapters that allow the coupling of molecules to nanostructures and their precise positioning on the scale of a millionth of a millimeter.
This development is of relevance especially for DNA sequencing, which is considered the key technology for the analysis of inherited diseases. The latest results are presented in the current issue of the journal “Nano Letters”.
Immobilization strategy: DNA origami (grey rectangles) equipped with a fluorescent dye (red) occupy the small holes in the metal film (ZMWs) in a way that only one adapter fits per cavity.
Comparison between optimal Poisson distribution and the experimentally measured distribution in ZMWs of 200 nm.
For DNA sequencing, individual nucleotides are analyzed which are the building blocks of DNA. “Monitoring the incorporation of single nucleotides into a full DNA strand in real-time is a revolutionary method”, Prof. Philip Tinnefeld explains. “It’s almost a live broadcast”.
Special proteins, the so-called DNA polymerases, incorporate the nucleotides in a zipper like fashion to build a double stranded DNA strand. In order to observe this process and extract the order of nucleotides, scientists employ special cover slides. A glass slide is coated with a thin metal film that contains tiny holes, so-called zeromode waveguides (ZMWs).
“The challenge for this application is to equip each of these nano-holes with exactly one polymerase that utilize the nucleotides”, Prof. Philip Tinnefeld says. Usually, these biomolecules are deposited randomly in the ZMWs, which results in many empty ZMWs while others contain multiple polymerase molecules. Even for the optimal situation, only 37 % of the holes can be used, as the expert for Nano-Bio-Sciences explains.
Coupling and positioning of molecules
His research group now achieved a more efficient usage of the ZMWs by developing a new binding strategy. For this, the nano-experts from the Institute for Physical and Theoretical Chemistry in the Laboratory of Emerging Nanometrology (Braunschweig University of Technology) could use their experience of working with the so-called DNA origami technique: the Braunschweig scientists literally fold precisely fitting structures from single viral DNA strands.
The nano-adapters were designed such that exactly one DNA origami can bind in every ZMW. The nano-adapters additionally provide docking points for functional units, like fluorescent dyes or the polymerase molecules that are used for DNA sequencing. “With our novel strategy, we connect single molecules via DNA origami with the lithographically fabricated ZMWs. This procedure can improve the efficiency of DNA sequencing and also be beneficial for applications in other areas of research like molecular electronics”, Prof. Tinnefeld summarizes.
About the project
This research project of the NanoBioSciences group of Prof. Philip Tinnfeld (Institute for Physical and Theoretical Chemistry) was conducted at the new Laboratory of Emerging Nanometrology of the Braunschweig University of Technology and was funded by a Starting Grant of the European Research Council (SiMBA).
E. Pibiri, P. Holzmeister, B. Lalkens, G.P. Acuna, P. Tinnefeld (2014):Single-Molecule Positioning in Zeromode Waveguides by DNA Origami Nano-Adapters - Nano Lett.
Prof. Philip Tinnefeld
Dr. Guillermo Acuna
Institut für Physikalische und Theoretische Chemie
Laboratory of Emerging Nanometrology
Technische Universität Braunschweig
Tel: 0531 391 5330
Stephan Nachtigall | idw - Informationsdienst Wissenschaft
Learning from Nature: Genomic database standard alleviates search for novel antibiotics
02.09.2015 | Max-Planck-Institut für marine Mikrobiologie
Orang-utan females prefer cheek-padded males
02.09.2015 | Max Planck Institute for Evolutionary Anthropology, Leipzig
China's Loess Plateau was formed by wind alternately depositing dust or removing dust over the last 2.6 million years, according to a new report from University of Arizona geoscientists. The study is the first to explain how the steep-fronted plateau formed.
China's Loess Plateau was formed by wind alternately depositing dust or removing dust over the last 2.6 million years, according to a new report from...
The leaves of the lotus flower, and other natural surfaces that repel water and dirt, have been the model for many types of engineered liquid-repelling surfaces. As slippery as these surfaces are, however, tiny water droplets still stick to them. Now, Penn State researchers have developed nano/micro-textured, highly slippery surfaces able to outperform these naturally inspired coatings, particularly when the water is a vapor or tiny droplets.
Enhancing the mobility of liquid droplets on rough surfaces could improve condensation heat transfer for power-plant heat exchangers, create more efficient...
Longer, more severe, and hotter droughts and a myriad of other threats, including diseases and more extensive and severe wildfires, are threatening to transform some of the world's temperate forests, a new study published in Science has found. Without informed management, some forests could convert to shrublands or grasslands within the coming decades.
"While we have been trying to manage for resilience of 20th century conditions, we realize now that we must prepare for transformations and attempt to ease...
A University of Oklahoma astrophysicist and his Chinese collaborator have found two supermassive black holes in Markarian 231, the nearest quasar to Earth, using observations from NASA's Hubble Space Telescope.
The discovery of two supermassive black holes--one larger one and a second, smaller one--are evidence of a binary black hole and suggests that supermassive...
A team of European researchers have developed a model to simulate the impact of tsunamis generated by earthquakes and applied it to the Eastern Mediterranean. The results show how tsunami waves could hit and inundate coastal areas in southern Italy and Greece. The study is published today (27 August) in Ocean Science, an open access journal of the European Geosciences Union (EGU).
Though not as frequent as in the Pacific and Indian oceans, tsunamis also occur in the Mediterranean, mainly due to earthquakes generated when the African...
20.08.2015 | Event News
20.08.2015 | Event News
19.08.2015 | Event News
02.09.2015 | Physics and Astronomy
02.09.2015 | Life Sciences
02.09.2015 | Awards Funding