Implantable Electronic Could Warn Patients of Early Stage Organ Transplant Rejection

Researchers may not be far away from finding a way to put low-cost, implantable electronic devices into humans that could potentially aid in organ transplants.

According to researchers from Ohio State University, the device would work by providing direct contact inside the body with living tissue that could begin to detect the early stages of organ transplant rejection.

Paul Berger, a professor of electrical and computer engineering and physics at the university, said that there are still certain obstacles that could prevent researchers from going forward with the device. For instance, he notes, according to a press release, that while most existing electronics are based on silicon, electrolytes in the body often interfere with electrical signals that may stem from the silicon circuits. And, other products used to create the device could be more expensive and harder to manufacture, according to Berger.

 "Silicon is relatively cheap... it's non-toxic," Berger said, via the release. "The challenge is to bridge the gap between the affordable, silicon-based electronics we already know how to build, and the electrochemical systems of the human body."

However, Berger and his colleagues believe they can make it work.

According to their study, silicon circuits were coated with the technology and continued to function, even after a 24 hour period in a solution that mimicked typical body chemistry.

The body's electrolytes, which carry sodium and potassium, control nerves and muscles that help maintain hydration. These responses are important to various chemical reactions within the body. Yet these reactions attract the electrolytes attractive to silicon, which is ready to, in turn, absorb them. Berger notes that once silicon is inside the body, the charges alter the electronic behavior of the silicon so that the readings are inconsistent and possibly false.

In this case, Berger and his colleages set out to test whether electrolytes could be blocked from entering silicone with a layer of aluminum oxide.

To do this, they submerged coated sensors in fluid for a 24 hour period, removed them from the solution and then ran a voltage across to see if they were in proper working order. The tests showed that the oxide coating effectively blocked electrolytes from the solution so sensors could remain fully functional.

Berger and colleagues see this as a great success for the future. This device could be used to detect certain proteins that the body produces when it is preparing to reject a transplanted organ.

According to the release, doctors would "insert a needle into the patients body near the site of the implanted organ. Silicon sensors on the needle would detect the protein, and doctors would know how to tailor the patients dosage of anti-rejection drugs based on the sensor readings."

As organ rejection can even result in death, devices like these could help predict problems earlier, according to researchers, and help save lives.

Some common symptoms that may suggest the rejection of an organ include an organ's inability to function properly, general discomfort, pain in the region of the organ, fever, or flu-like symptoms.