Small but Mighty: Canadian Microrobot Learns to “Dissolve” Kidney Stones Silently
Engineers at the University of Waterloo in Canada have demonstrated what truly “soft” robotic medicine looks like. Their magnetic microrobot — essentially a flexible hydrogel-based strip about one centimeter long and a millimeter thick, roughly the size of a grain of rice — is capable, under the control of an external magnetic field, of reaching a kidney stone within the urinary tract and breaking it down precisely, without traditional shock waves or invasive tools.
Instead of surgery, doctors insert this “robotic strip” through a catheter into the bladder and then guide it along a three-dimensional model of the urinary tract using a robotic magnetic navigation system and real-time ultrasound. Built-in micromagnets allow the robot to crawl through the complex geometry of the ureter, while an integrated enzyme (urease) locally alters the pH of the surrounding fluid. The stone is not shattered abruptly but gradually dissolves and disintegrates into small fragments, which are then naturally excreted by the body.
Laboratory tests conducted in a 3D-printed model of the human urinary system showed a marked acceleration in the dissolution of uric acid stones and a strong potential for pain reduction: the robot acts only on the stone, leaving healthy tissues virtually untouched.
For healthcare systems, this is more than an impressive experiment — it is an attempt to address a growing problem. Kidney stones are among the most common urological disorders, affecting an estimated 12% of the global population and showing a high recurrence rate. Today, patients are often treated for years with painkillers and long-term medications, and in acute cases, surgery remains the only option. If future preclinical and clinical studies confirm the current results, magnetic soft microrobots could become an alternative to surgical stone removal and set a new standard for gentle, minimally invasive robotic interventions in urology.
More about the project and the research team is available on the University of Waterloo website:
https://uwaterloo.ca/news/media/soft-robots-go-right-site-kidney-stones
