If you add DNA to a liquid, you can make it swirl and churn in tiny pipes where turbulence is supposed to be impossible.
arXiv · March 18, 2026 · 2603.15890
The Takeaway
At the micro-scale, fluids usually flow smoothly like honey, making mixing nearly impossible. Researchers found that adding long molecules like DNA creates 'viscoelastic waves' that churn the fluid, offering a way to mix chemicals in tiny devices without any moving parts.
From the abstract
Mixing at the microfluidic scale is challenging due to the low Reynolds numbers and often high Péclet numbers. Without turbulence, mixing relies solely on diffusion, resulting in slow and inefficient mixing. We demonstrate enhanced mixing in a simple Y-shaped microfluidic channel using viscoelastic turbulence in fluids containing macromolecules, suchas DNA and polyethyleneoxide. We investigated mixing at two distinct scales: the mixing of small molecules and the mixing of polymers. We show how t