March 27, 2012

Skin Patches Tell All

(Ivanhoe Newswire)-- Ultra thin patches that can detect medical problems are now replacing the grueling test procedures in doctor's offices.

With patients hooked to machines by uncomfortable wires or pins attached to the skin with gels or tape that can be painful to remove and can leave a sticky residue. More importantly, the tests detect brain, heart and muscle activity while patients are in a medical setting, rather than carrying out activities of everyday life, Dr. John Rogers, Ph.D., was quoted as saying.

"A key feature of our epidermal electronics is its natural interface to the body, without wires, pins, adhesives or gels, to allow a much more comfortable and functional system," Rogers said. "The technology can be used to monitor brain, heart or muscle activity in a completely noninvasive way, while a patient is at home."

Patients can't feel the electronic skin patches on their skin because they are about the thickness of a human hair. They could even be covered up with a real temporary tattoo. Despite their small size, the patches can pack full-scale electronic circuits needed to monitor health status with wireless capabilities that can, with future development, be used to transmit data to the patient's cell phone and on to the doctor's office.

The patches are applied to the skin just like a temporary tattoo, with water and a backing that peels off. The first versions wore off after a day or sooner if they got wet. The latest version is applied in the same way, but a modified form of the spray-on bandages sold in drugstores is applied over the patch. The spray protects the circuit from water and normal wear-and-tear and keeps it on the skin for up to a week. In this format, the devices can accommodate transpiration, sweat and even washing with soapy water.

"We've also figured out how to make the devices operate in a bi-directional way," Rogers explained. "The older devices only measure what's going on in the body. Our newest patch can measure muscle activity and stimulate the muscles. That's useful for rehabilitation after an accident or long periods of bed rest or even for helping people move prosthetic limbs more easily." And with plans to add Wi-Fi capabilities, electronic skin could also send information back to a physician.

Rogers co-founded a company called mc10 which is further advancing the technology and putting the patches on medical instruments that go inside the body, such as catheters, which are balloon-like tubes used in heart surgery. The electronic skin patch is placed on the outside surface of the catheter. When the catheter expands in the heart, the patch expands with it and touches the inside of the heart, taking measurements used to guide surgery.

Rogers said the patches also could have applications in other areas such as allowing monitoring and depth-profiling of skin hydration, with relevance in sports, skin-care and cosmetics for consumers.

SOURCE: 243rd National Meeting & Exposition of the American Chemical Society (ACS), March 2012