Take your expensive mobile telephone to the beach, jump into the salt water with it. Count the seconds before it stops working forever. The human body is mostly salt water. Implantable bionics contain many of the circuit elements in mobile telephones (chips, resistors, capacitors, etc.) that must live in salt water for its functional lifetime. Hermetic encapsulation involves surrounding circuit elements in such a way that water molecules cannot penetrate into and damage the electronics. At UNSW we are performing leading edge research, some in collaboration with Cochlear Limited to establish small, implantable devices that will last a lifetime.
Nerves can respond to electric impulses by sending signals called 'Action Potentials' or releasing chemicals called Neurotransmitters. To deliver the electrical impulses to the nerves, an interface must be established. At UNSW we are using Laser Technologies, Micro Machining approaches and Novel Conductive Polymers to create the next generation of Neural interfaces to enable implantable bionics to advance to treat more diseases, alleviate more pain, and restore more senses than ever before.
The computer era has ushered in extraordinary advances in Microelectronics. The mechanical world has struggled to keep up with these advances, but our research at UNSW aims to advance fabrication processes to meet the challenges of the Microelectronics era. Recently, we have introduced 'chip-scale' implants to our research programs. With these we combine our Hermetic Encapsulation with Microelectronics to integrate the two and produce implantable bionics far smaller than a fingernail. These will be easier to implant, and will be able to interface with neurons never before accessible. This will usher in a new era of implantable bionic therapies that simply weren't possible just a few years ago.
Focused light can be used to machine material with incredible precision. We use different wavelengths of light to selectively remove certain materials while leaving others untouched. This allows us to create very complex neural interfaces that enable never before possible therapies to be realised. Using controlled impulses onto the surface of electrodes, we can significantly improve their surface characteristics to allow them to carry more electrical charge, and last longer inside the body.
For a medical implant to last within the human body for a lifetime, a special interface must be established between man-made materials and the implant recipient. At UNSW we're investigating new ways for materials to interact with their biological surroundings. This will allow us to build more complex implants by expanding the material options available to us in implant design, and to create a more robust human-machine interface.