Researchers control individual molecules for precision sensing

By combining two cutting-edge biological research methods, researchers have achieved near-perfect control over the manipulation of individual molecules, allowing them to be identified and characterized with unprecedented precision. Aleksandra Radenovic, head of the Laboratory of Nanoscale Biology in the School of Engineering, has worked for years to improve nanopore technology, which involves passing a molecule like DNA through a tiny pore in a membrane to measure an ionic current. Scientists can determine DNA's sequence of nucleotides - which encodes genetic information - by analyzing how each one perturbs this current as it passes through. Currently, the passage of molecules through a nanopore and the timing of their analysis are influenced by random physical forces, and the rapid movement of molecules makes achieving high analytical accuracy challenging. Radenovic has previously addressed these issues with optical tweezers and viscous liquids. Now, a collaboration with Georg Fantner and his team in the Laboratory for Bioand Nano-Instrumentation at EPFL has yielded the advancement she's been looking for - with results that could go far beyond DNA. "We have combined the sensitivity of nanopores with the precision of scanning ion conductance microscopy (SICM), allowing us to lock onto specific molecules and locations and control how fast they move.