Engineers from UNSW Sydney have discovered a way to create flexible electronic systems on ultra-thin skin-like materials.

The development allows entire stretchable 3D structures to operate like a semiconductor and could help significantly reduce the need for animal testing by making so-called organ-on-chip technology more effective.

The technology may also be used in wearable health monitoring systems or implantable biomedical applications.

The research team, led by Dr Hoang-Phuong Phan, have published their findings in the Advanced Functional Materials journal.

Their new process involves lithography - a technique that uses light to print tiny patterns - to fabricate wide bandgap semiconductors such as silicon carbide and gallium nitride onto very thin and flexible nanomembranes on a polymer substrate.

These membranes provide sensing, recording, and stimulation functionalities even while being stretched and twisted into any conceivable 3D shape.

The chips can replicate the functions and structures of organs, allowing scientists to study their behaviour and test the effects of drugs or diseases in a more accurate and efficient manner.
“Our process allows for an electronic system to be created on a membrane that can be stretched into any 3D shape around the organ-on-chip,” Dr Phan says. 

“You can grow 3D cell organs that mimic the organs in a real body, but we also need to develop 3D electrodes to help facilitate that organ-on-chip process.

“Many people are keen to move towards medical testing on replicated versions of human cells rather than live animals for legal, ethical and moral reasons.”

Dr Phan says there is interesting potential for the new process to significantly improve the quality of monitoring, diagnosis, and therapy.

One such function could be a wearable sleeve to help detect and signal alerts regarding the levels of UV radiation a person was being subjected to throughout the day, which could ultimately help lower the instances of skin cancer.

The UNSW team also propose their new material may be developed further to create implantable biomedical devices where the electrical system can monitor, and influence, neuron signals in real-time.

While this is years off being a possibility, the researchers are already planning further tests with the aim of potentially helping people who have epilepsy. 

“For people with epilepsy, when a seizure is just about to happen the brain will send out unusual signals which are the trigger,” Dr Phan says.

“If we can create an implantable electronic device that can detect those abnormal patterns, it can potentially also be used to apply electrical stimulation to bypass the seizure.”

One of the key challenges that needs to be overcome with regards to implantable devices is how to power such an electronic system.

Along these lines, researchers at UNSW are also trying to develop a magnetic resonance coupling system that could be integrated with the wide bandgap 3D electronic membranes to wirelessly transfer power through the body via an external antenna.