Untethered magnetic millirobot for targeted drug delivery

  • Veronica IacovacciEmail author
  • Gioia Lucarini
  • Leonardo Ricotti
  • Paolo Dario
  • Pierre E. Dupont
  • Arianna Menciassi


This paper reports the design and development of a novel millimeter-sized robotic system for targeted therapy. The proposed medical robot is conceived to perform therapy in relatively small diameter body canals (spine, urinary system, ovary, etc.), and to release several kinds of therapeutics, depending on the pathology to be treated. The robot is a nearly-buoyant bi-component system consisting of a carrier, in which the therapeutic agent is embedded, and a piston. The piston, by exploiting magnetic effects, docks with the carrier and compresses a drug-loaded hydrogel, thus activating the release mechanism. External magnetic fields are exploited to propel the robot towards the target region, while intermagnetic forces are exploited to trigger drug release. After designing and fabricating the robot, the system has been tested in vitro with an anticancer drug (doxorubicin) embedded in the carrier. The efficiency of the drug release mechanism has been demonstrated by both quantifying the amount of drug released and by assessing the efficacy of this therapeutic procedure on human bladder cancer cells.


Drug delivery system Drug-loaded hydrogel Magnetic robot Magnetic docking Microrobotics Targeted therapy 



The authors would like to thank Mr. Tommaso Mazzocchi for his support with Abaqus simulations, Mr. Nicodemo Funaro and the staff of The BioRobotics Institute mechanical workshop for 3D printing. This work was supported in part by the GeT Small project (TarGeted Therapy at Small Scale), funded by the Scuola Superiore di Studi Universitari e di Perfezionamento Sant'Anna (Pisa, Italy). Pierre Dupont acknowledges support by the US National Science Foundation under grant IIS-1208509 and by the Wyss Institute for Biologically Inspired Engineering.

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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Veronica Iacovacci
    • 1
    Email author
  • Gioia Lucarini
    • 1
  • Leonardo Ricotti
    • 1
  • Paolo Dario
    • 1
  • Pierre E. Dupont
    • 2
  • Arianna Menciassi
    • 1
  1. 1.The BioRobotics InstituteScuola Superiore Sant’AnnaPontederaItaly
  2. 2.Department of Cardiac Surgery, Boston Children’s HospitalHarvard Medical SchoolBostonUSA

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