A Mini-Patch Magnetic Insulin Pump for Enhanced Delivery Resolution and Accuracy

Insulin pumps typically use piston-based mechanisms with bulky transmission components to convert rotary motion into the piston's forward motion. These mechanical transmission systems and insulin reservoirs occupy more than one-third of pumps' volume, significantly limiting miniaturization and making pumps cumbersome for daily use. Herein, a compact, magnetically actuated insulin pump is developed that is less than one-quarter the size of piston-based pumps. Instead of bulky mechanical components, the pump uses a magnetic soft actuator to directly compress the insulin chamber, controlled by a precisely tuned electromagnetic field. This innovative design eliminates the need for large transmission systems, enabling a notably smaller form factor. In addition, the fine-tunable magnetic actuation enables a 0.01 μL delivery resolution, significantly surpassing the 0.25 μL resolution of piston-based pumps. This high-resolution mechanism facilitates further miniaturization by allowing the use of high-concentration insulins, thereby reducing the reservoir size. By varying the magnetic field's waveform, amplitude, and duration, the pump's performance can be further enhanced. The reported magnetic insulin pump exhibits superior repeatability and accuracy across single-pulse, basal, and bolus modes compared to commercial insulin pumps. This miniaturized, high-resolution magnetic insulin pump is anticipated to substantially benefit people with diabetes by improving portability, precision, and cost efficiency.