Engineers are developing a dissolvable brain sensor that measures pressure and temperature-A must read

A Dissolvable brain sensor could soon be used by neurosurgeons to monitor brain pressure and temperature in traumatic brain injury patients. Researchers have already tested the dissolvable brain sensor on live test subjects. According to research published in the journal Nature, the dissolvable brain sensor can be used before or after brain surgery and can even attempt to bring down pressure inside a patient’s brain before completely dissolving and absorbing into the body.


Engineers and neurosurgeons at the University of Illinois in Champaign, Illinois, and Washington University School of Medicine in St. Louis, Missouri, developed the dissolvable brain sensor with funding provided by the Howard Hughes Medical Institute, NIH, and DARPA. Professor John A. Rogers worked with the team for several years to help develop the small, thin, wireless silicon sensor. Rogers works as a physical chemist from a lab at the University of Illinois and specializes in working with soft, pliable, inexpensive material over stronger but more expensive material.

Along with wireless, injectable optofluidic needles and auricle-mounted electrodes, the silicon hybrid combination dissolvable brain sensor is noted as a 2014-15 highlight for the Rogers Research Group. One co-author of the study published on the Nature website, Rory K. J. Murphy, says that biomedical applications of electronic devices are rapidly developing. Murphy went on to say that standard electronic implants have a history of causing infection, inflammation, and immune reaction inside the body.

“A major hurdle has been that implants placed in the body often trigger an immune response, which can be problematic for patients.”

Conventional implants can also move around within the body and surgical removal poses other health risks for patients. But the new dissolvable brain sensor does its job, dissolves, and then the body absorbs it, a process that could take several days. Made of silicon and poly lactic-co-glycolic acid (PLGA), a Food and Drug Administration approved biodegradable and biocompatible copolymer, the dissolvable brain sensor was first tested in a saline solution, where it dissolved in a couple of days. Researchers then moved on to testing it in live laboratory rats, where it functioned successfully and eventually completely dissolved inside the rats’ brains.

Testing now reportedly moves on to live human patients who suffer from either brain illnesses or traumatic brain injuries. Study co-author and neurosurgeon Rory Murphy says he deals with brain trauma all the time, ranging from blood clots to bullets to blunt force trauma. In these events, brain swelling can lead to death or permanent brain damage. Murphy helped develop the new dissolvable brain sensor to take the place of the large, cumbersome existing sensors.

“The benefit of these new devices is that they dissolve over time, so you don’t have something in the body for a long time period, increasing the risk of infection, chronic inflammation and even erosion through the skin or the organ in which it’s placed,” said Murphy.

Supposedly tiny and thinner than a needle tip, the dissolvable brain sensor takes accurate temperature and pressure readings inside the brain for several days, up to a week, before naturally dissolving in cerebrospinal fluid and resorbing back into surrounding soft tissue within a day. Separate pressure and temperature sensors are integrated into the silicon chip that sits on the brain’s surface and is connected to a wireless transmitter on the outside of the skull. Wireless data transmitted from the dissolvable brain sensor has so far shown to be just as accurate as its existing counterparts.

The study published in March 2015 suggests that the dissolvable brain sensor might eventually be used in other parts of the body and can be adapted for other uses, such as deep brain stimulation or dispensing medicine. Rogers has been working for years on disappearing technology to be used in consumer gadgets and the human body using water-soluble silicon. Murphy read about the work Rogers was doing in 2012 and thought it would be perfect for what he does as a neurosurgeon, saying the ultimate strategy is to have a device you can place inside body organs that can monitor the health of the organ and transmit signals wirelessly.

“And then after the critical period that you actually want to monitor, it will dissolve away and disappear.”