A team led by Sandia National Laboratories researchers has developed a new manufacturing technique that puts a critical kink into the lumen of a nanopore. Due to their natural properties, nanopores, which are only slightly larger than DNA molecules, one day might be used to comprehensively characterize DNA, RNA, and proteins passing through. A consistent problem with nanopores has stemmed from the fact that DNA passes too quick through them, but a new technique of placing a kink inside the nanopores slows down the DNA passing through five fold.
From a Sandia press release:
Combined with atomic-layer deposition to modify the chemical characteristics of the nanopores, the innovations achieve a fivefold slowdown in the voltage-driven translocation speeds critically needed in DNA sequencing.
“By control of pore size, length, shape and composition,” says lead researcher Jeff Brinker, “we capture the main functional behaviors of protein pores in our solid-state nanopore system.”
The idea of using synthetic solid-state nanopores as single-molecule sensors for detection and characterization of DNA and its sister materials is currently under intensive investigation by researchers around the world. The thrust was inspired by the exquisite selectivity and flux demonstrated by natural biological channels. Researchers hope to emulate these behaviors by creating more robust synthetic materials more readily integrated into practical devices.
Current scientific procedures align the formation of nominally cylindrical or conical pores at right angles to a membrane surface. These are less capable of significantly slowing the passage of DNA than the kinked nanopores.
“We had a pretty simple idea,” Brinker says. “We use the self-assembly approaches we pioneered to make ultrathin membranes with ordered arrays of about 3-nanometer diameter pores. We then further tune the pore size via an atomic-layer deposition process we invented. This allows us to control the pore diameter and surface chemistry at the subnanometer scale. Compared to other solid state nanopores developed to date, our system combines finer control of pore size with the development of a kinked pore pathway. In combination, these allow slowing down the DNA velocity.”
Link: Kinked nanopores slow DNA passage for easier sequencing…
Abstract in Nature Materials: DNA translocation through an array of kinked nanopores