Synopsis

Electronic Tagging for Cells

Physics 10, s82
Researchers have made a radio-frequency identification device that fits inside a cell.
X. Hu et al., Phys. Rev. Applied (2017)

Electronic tags in the form of radio-frequency identification (RFID) devices are everywhere. They show up in key cards, e-passports, toll passes, you name it. H.-S. Philip Wong, Ada Poon, and colleagues at Stanford University, California, have now made an RFID tag that is small enough to be placed inside a cell. Such tags might one day be used to track and monitor individual cells wirelessly.

RFID systems consist of two main components: a tag attached to the object being identified and a transceiver that is located a short distance away. The transceiver sends wireless radio waves to the tag, and the tag—made up of a microchip and an antenna—responds with its unique identifying information. The tag’s size is mostly determined by the antenna, which is typically on the centimeter- to millimeter-diameter scale—too big to be embedded into cells.

Building on recent advances in nanofabrication and wireless powering of millimeter-scale electronic implants, Wong and colleagues have made a micrometer-scale RFID system. The device contains a tag that is only 22 𝜇m in diameter and two transceivers that are each roughly twice the tag’s diameter. The team showed that this novel two-transceiver design greatly increases the tag’s rf-signal magnitude by more than tenfold relative to the traditional single-transceiver design. They also showed that mouse melanoma cells can swallow the tag and remain intact. Future work will involve pumping RFID-tagged cells through a microfluidic channel and measuring their rf signals, one at a time, with the transceivers placed right underneath the channel. It will also include adding special sensors that affect the rf signals in response to changes in cellular parameters such as the pH level.

This research is published in Physical Review Applied.

­–Ana Lopes

Ana Lopes is a Senior Editor of Physics.


Subject Areas

ElectronicsBiological PhysicsMedical Physics

Related Articles

Tension Remodeling Resolves Tissue Architecture Question
Soft Matter

Tension Remodeling Resolves Tissue Architecture Question

A dynamical tension model captures how cells swap places with their neighbors in epithelial tissues, explaining observed phase transitions and cellular architectures. Read More »

Two Experimental Observations of Helix Reversals
Materials Science

Two Experimental Observations of Helix Reversals

Helical bacteria and corkscrew rods can both undergo handedness reversals that could be useful in future robotic systems. Read More »

Model Reveals Reptilian Scale Pattern
Biological Physics

Model Reveals Reptilian Scale Pattern

Researchers have predicted—and confirmed—a secondary pattern on the ocellated lizard’s scales that is too subtle for our eyes to see. Read More »

More Articles