Electricity flows through an atom-sized hole at the exact same speed, no matter how much salt is in the water.
March 24, 2026
Original Paper
Invariant ionic conductance in an atomically thin polar nanopore
arXiv · 2603.21827
The Takeaway
Usually, adding more salt to water makes it conduct electricity better because there are more ions to carry the charge. In this experiment, a hole only one atom thick broke this law, keeping the flow exactly the same across a million-fold change in salt concentration, mimicking the mysterious way biological cells control their internal chemistry.
From the abstract
Ion channels regulate many essential properties of biological cells, especially the membrane potential. Despite decades of efforts on artificial channels, it remains a great challenge to mimic the dipole potential-an indispensable constituent of the membrane potential, due to its angstrom-scale characteristic length. Here, we explore nanopores in monolayer molybdenum sulfide selenide (MoSSe) considering its intrinsic dipole and atomic thickness. Remarkably, an invariant ionic conductance was obs