Scientists in Sweden created a tiny DNA-based nanorobot that can kill cancer cells with incredible precision—only releasing its “lethal weapon” in the acidic environment surrounding tumors, while leaving healthy cells untouched. This breakthrough could one day lead to cancer treatments with fewer side effects compared to traditional therapies.
The nanorobot, developed at the Karolinska Institutet, uses a technology called DNA origami, which folds DNA into specific shapes at the nanoscale. Inside the structure, researchers hid six cancer-killing peptides arranged in a hexagon. These peptides activate only when they detect a drop in pH, which is common in the microenvironment of solid tumors. At the normal pH level of healthy tissue (around 7.4), the weapon stays hidden. But when the pH drops to about 6.5—typical of tumors—the peptides are exposed and destroy nearby cancer cells.
When tested in mice with breast cancer, the nanorobot reduced tumor growth by 70% compared to mice that received an inactive version. Importantly, it did so without damaging healthy tissue. The researchers now aim to improve the robot’s precision by adding elements that can bind specifically to certain cancer types, and to better understand potential side effects before moving to human trials.