Scientists at the Swiss Federal Institute of Technology in Lausanne have developed a new technology to create DNA molecules that bind to viral proteins more precisely and tightly than traditional antibodies. Their work is published in Nature Nanotechnology.
These are aptamers—short strands of DNA or RNA that can selectively bind to specific molecules. Used in diagnostics and therapy, they offer advantages over antibodies: they can be synthesized in the laboratory, making them cheaper and more stable.
However, until now, aptamers have typically been single-stranded, meaning they bind to only one site on a target protein. This limitation has reduced their effectiveness against viruses like SARS-CoV-2, whose proteins are composed of three identical segments, known as trimers.
The researchers addressed this problem with a method called MEDUSA (Multivalent Evolved DNA-based SUpramolecular Assemblies). It enables the creation of multimeric aptamers capable of simultaneously binding to multiple sites on a viral protein. As a result, they become tens to thousands of times more effective than traditional molecules.
“We were inspired by the natural mechanisms through which viruses interact with cells and applied this principle to synthetic biotechnology,” said Maartje Bastings, head of the laboratory.
The new technology could be used to diagnose infectious diseases and develop new treatments. In the future, the researchers plan to reduce processing time and apply the approach to more complex viruses, such as dengue and anthrax.
