MagnetoSperm performs a flagellated swim using weak oscillating magnetic fields.
A team of researchers at the University of Twente (Netherlands) and German University in Cairo has developed sperm-inspired microrobots that can be controlled by weak oscillating magnetic fields.
Described in a cover article in AIP Publishing’s journal Applied Physics Letters, the 322 micron-long robots consist of a head coated in a thick cobalt-nickel layer and an uncoated tail.
When the microrobot is subjected to an oscillating field of less than five millitesla — about the strength of a decorative refrigerator magnet — it experiences a magnetic torque on its head, which causes its flagellum to oscillate and propel it forward.
The researchers are then able to steer the robot by directing the magnetic field lines towards a reference point. The propulsion mechanism allows for swimming at an average speed of about 158 microns/second with a weak 45 Hz magnetic field.
Islam Khalil, PhD, an Assistant Professor of the German University in Cairo, designed the MagnetoSperm microrobots along with Sarthak Misra, PhD, and colleagues at MIRA-Institute for Biomedical Technology and Technical Medicine at the University of Twente.
“Nature has designed efficient tools for locomotion at micro-scales. Our microrobots are either inspired from nature or directly use living micro-organisms such as magnetotactic bacteria and sperm cells for complex micro-manipulation and targeted therapy tasks,” said Misra, the principal investigator of this study, and an associate professor at the University of Twente.