They can be implanted in the body

Nov 3, 2009 14:03 GMT  ·  By
This clear silk film, about one square centimeter, has six silicon transistors on its surface. These flexible devices can be implanted in mice like the one in this image without causing any harm
   This clear silk film, about one square centimeter, has six silicon transistors on its surface. These flexible devices can be implanted in mice like the one in this image without causing any harm

For a very long time, scientists have dreamed about combining electronics with the human body, and now it would appear that they have succeeded. A group of experts managed to create a type of circuit that essentially dissolved into the human body. The way they accomplished that was by combining thin, flexible silicon electronics with silk substrates. The innovative work went as far as creating arrays of transistors that were based entirely on thin films of silk, Technology Review reports.

The main role of the fabric is to ensure that the circuits are in tune with the body. Other circuits, for example, need to be protected when inserted into a living organism, but the new, silicon-based ones do not. Over a period of time, the silk melts away inside the body and only the silicon wires remain. However, they do not cause irritations, because they are only nanometers thick, and, therefore, nearly inexistent. “Current medical devices are very limited by the fact that the active electronics have to be 'canned,' or isolated from the body, and are on rigid silicon,” University of Pennsylvania Associate Professor of Neurology and Bioengineering Brian Litt says.

The expert is part of the silk-silicon group that is currently working on developing medical applications for the new devices. There are virtually limitless possibilities for the new devices, experts believe. For starters, scientists may insert LEDs under the skin that could light up in a certain color when blood-sugar levels in diabetic patients drop too low. Additionally, electrodes that can interface with the human brain may also become possible shortly. The main advantage that the new instruments would have would be that they are very comfortable. Their reduced sizes and elasticity makes them suitable for long-term use.

The new work builds on previous studies by scientists at the University of Illinois in Champaign-Urbana (UIUC) Beckman Institute, who developed stretchable, bendable silicon circuits that maintained the same level of performance as their rigid, silicon-based counterparts. Tufts University Professors of Bioengineering Fiorenzo Omenetto and David Kaplan then collaborated with the UP team, in order to make these circuits work in sync with the human body. The two TU researchers announced last year that they had been able to obtain optical devices from silkworm-cocoon proteins.