By Will Soutter
A multi-institute research team has created a synthetic nanotube that functions as a nanoscale sieve as it allows selective ion transport like Mother Nature's potassium ion channels, which are essential components of almost all living cells.
Computer-generated image of the artificial potassium ion channel
The research team comprising research group of Xiao Cheng Zeng from the University of Nebraska-Lincoln (UNL); research group of Bing Gong from the Beijing Normal University and University at Buffalo; and research group of Zhifeng Shao, Executive Dean of Shanghai Jiao Tong University’s Center for System Biomedicine created the nanotubes and computed the ion flow, concluding a three-year project largely funded by the National Science Foundation (NSF). X-ray work was carried out at the Advanced Photon Source at Argonne National Laboratory.
Zeng's research group conducted computations to explore the structure of the nantoube at UNL's Holland Computing Center using the funding from the Nebraska Research Initiative and NSF. Zeng’s team measured the size and the distance between the rings to determine the device structure, and discovered that the molecules can be stacked in eight possible ways. The team also found that these structures demonstrated stability at room temperature.
The synthetic nanotube possesses the same diameter and demonstrates hydrophobic and self-assembling properties, which are vital for medical and industrial advancements. Zeng informed that this nanotube can be observed as a stack of multiple rings and is very accurate. It is a uniform subnanometer pore with a size of 8.8 Å and imitates Mother Nature's potassium pore that allows larger-sized potassium ions but not smaller-sized sodium ions.
Nevertheless, the mechanism behind the selective potassium ion transport is still under investigation. For researchers, desalination and drug delivery are the area of interest in this field. The research team’s next step is to functionalize the nanotube’s inner wall in order to add more selectivities.