Highlight September 2008: Nano2Life Best Publication Award 2008 for Georgette Salieb-Beugelaar.

At the final scientific meeting of Nano2Life in Heraklion (Greece) the paper published in Nano Letters July 2008, presenting our recent DNA work, was awarded with the “Nano2Life Best Publication 2008”. This work was funded by Nano2Life and NanoNed.

Field Dependent Mobility of DNA in 20 nm High Nanoslits

The transport behavior of λ-DNA (48 kbp) in fused silica nanoslits is investigated upon application of electrical ﬁelds of different strengths. The slit dimensions are 20 nm in height, 3 µm in width, and 500 µm in length. With ﬁelds of 30 kV/m or below, the molecules move ﬂuently through the slits, while at higher electrical ﬁelds, the DNA molecules move intermittently, resulting in a strongly reduced mobility. We propose that the behavior can be explained by mechanical and/or ﬁeld-induced dielectrophoretic DNA trapping due to the surface roughness in the nanoslits. The observation of preferential pathways and trapping sites of the λ-DNA molecules through the nanoslits supports this hypothesis and indicates that the classical viscous friction models to explain the DNA movement in nanoslits needs to be modiﬁed to include these effects. Preliminary experiments with the smaller XbaI-digested litmus-DNA (2.8 kbp) show that the behavior is size-dependent, suggesting that the high ﬁeld electrophoresis in nanoslits can be used for DNA separation.

nanoslits

Above: In the nanoslits, DNA molecules are being trapped. Possible explanations could be the influence of the surface roughness, resulting in steric trapping and dielectrophoretic trapping.

The web release date was the 5^th of April and presented in Nano Letters July 2008.