Researchers embrace imperfection to improve biomolecule transport

7 August 2019

While watching the production of porous membranes used for DNA sorting and sequencing, University of Illinois researchers wondered how tiny steplike defects formed during fabrication could be used to improve molecule transport. They found that the defects - formed by overlapping layers of membrane - make a big difference in how molecules move along a membrane surface. Instead of trying to fix these flaws, the team set out to use them to help direct molecules into the membrane pores. Their findings are published in the journal Nature Nanotechnology.

Physics professor Aleksei Aksimentiev, left, and graduate student Manish Shankla. (Photo by L. Brian Stauffer)Physics professor Aleksei Aksimentiev, left, and graduate student Manish Shankla. (Photo by L. Brian Stauffer)

The Dutch Research Council supported this research through a Visitor's Travel Grant for prof Aleksei Aksimentiev.  While on sabbatical at Delft University of Technology in the Netherlands, Aksimentiev found that DNA tends to accumulate and stick along the edges of fabrication-formed defects that occur as linear steps spanning across the membrane’s surface. The Illinois team’s goal was to find a way to use these flaws to direct the stuck molecules into the nanopores, as a principle that can also apply to the delivery, sorting and analysis of biomolecules.

Read the full article here.

Laboratory-engineered membrane defects with edges that spiral downward would give biomolecules like DNA, RNA and proteins no other option than to sink into a nanopore for delivery, sorting and analysis. (Graphic courtesy Manish Shankla)Laboratory-engineered membrane defects with edges that spiral downward would give biomolecules like DNA, RNA and proteins no other option than to sink into a nanopore for delivery, sorting and analysis. (Graphic courtesy Manish Shankla)

To reach prof Aleksei Aksimentiev: aksiment@illinois.edu.

The paper “Step-defect guided delivery of DNA to a graphene nanopore” is available online and from the U. of I. News Bureau. DOI: 10.1038/s41565-019-0514-y

Source: University of Illinois