Molecular biologists, including the cool dudes from CSI, use gel electrophoresis to separate DNA fragments from each other in order to analyse the DNA.
A team of researchers under the leadership of Vici winner Serge Lemay, has now shown for the first time how the gel influences the movement of the DNA. The researchers drove a single DNA molecule through a nanopore in order to analyse the forces on the DNA. The results of the research were published on 29 March in Nature Physics.
The movement of DNA under the influence of an electric field, electrophoresis, is caused by negatively charged groups in the basic structure of the DNA. These negative charges are shielded by positive ions, that accumulate in a layer around the DNA. These ions retard the movement of DNA under the influence of an electric field. The electrostatic forces and counteracting friction of the gel are inextricably linked to each other. Therefore up until now it seemed impossible to investigate these two factors independently.
The measurements revealed that the retarding forces exerted by the ions, slowly decreased if the DNA moved through a larger nanopore. The bigger the pore the smaller the resistance. Calculations based solely on electrostatic forces had yielded other expectations. The hydrodynamic environment was found to exert a greater influence than had been expected.
The team used a unique combination of different techniques. This combination formed a good basis for highly promising developments in single molecule techniques based on nanopores. For example, such techniques render the detailed detection of the interaction between proteins and DNA possible.
The first author of the article in Nature Physics is Stijn van Dorp of Delft University of Technology. The research was carried out by an international team of top researchers. Serge Lemay received a Vici grant from NWO. Cees Dekker received the prestigious NWO/Spinoza Award in 2003. Nynke Dekker received a Vidi grant from NWO.Nature publication
Serge Lemay | EurekAlert!
'Frequency combs' ID chemicals within the mid-infrared spectral region
16.03.2018 | American Institute of Physics
Fraunhofer HHI have developed a novel single-polarization Kramers-Kronig receiver scheme
16.03.2018 | Fraunhofer-Institut für Nachrichtentechnik, Heinrich-Hertz-Institut, HHI
Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...
On 15 March, the AWI research aeroplane Polar 5 will depart for Greenland. Concentrating on the furthest northeast region of the island, an international team...
The world’s second-largest ice shelf was the destination for a Polarstern expedition that ended in Punta Arenas, Chile on 14th March 2018. Oceanographers from...
At the 2018 ILA Berlin Air Show from April 25–29, the Fraunhofer Institute for Laser Technology ILT is showcasing extreme high-speed Laser Material Deposition (EHLA): A video documents how for metal components that are highly loaded, EHLA has already proved itself as an alternative to hard chrome plating, which is now allowed only under special conditions.
When the EU restricted the use of hexavalent chromium compounds to special applications requiring authorization, the move prompted a rethink in the surface...
At the ILA Berlin, hall 4, booth 202, Fraunhofer FHR will present two radar sensors for navigation support of drones. The sensors are valuable components in the implementation of autonomous flying drones: they function as obstacle detectors to prevent collisions. Radar sensors also operate reliably in restricted visibility, e.g. in foggy or dusty conditions. Due to their ability to measure distances with high precision, the radar sensors can also be used as altimeters when other sources of information such as barometers or GPS are not available or cannot operate optimally.
Drones play an increasingly important role in the area of logistics and services. Well-known logistic companies place great hope in these compact, aerial...
16.03.2018 | Event News
13.03.2018 | Event News
08.03.2018 | Event News
16.03.2018 | Earth Sciences
16.03.2018 | Physics and Astronomy
16.03.2018 | Life Sciences