In recent years, organic bioelectronics has emerged as a potentially disruptive technology, introducing innovative devices with unprecedented features of biocompatibility and functionality. The potential of organic materials resides not only in their favorable mechanical properties, which comply to those of biological tissues, but also on their ability to enable mixed electronic and ionic transport and on the possibility to finely tune their optoelectronic properties, such as optical absorption, charge photogeneration and transport. Similarly, the development of organic optoelectronic devices, largely employed in light-emitting and photovoltaic technologies (e.g. OLEDs and OPVs), has led in recent years to the creation of a number of bioelectronic light and image sensors able to restore or mimic human vision.
In addition, the synthesis of organic compounds can be tuned to further improve biocompatibility and to allow for chemical or biochemical functionalization (bioconjugation), as well as to enable cost-effective and scalable processability of materials. For these reasons, a plethora of biocompatible, mechanically compliant, large area, multipoint biosensing and stimulating devices are now available. Existing technologies range from either chronic or transient implantable biosensors and drug-delivery systems, to electronic transducers for in vitro and in vivo neuronal activity, artificial retinas, ion pumps and ingestible devices. Moreover, organic neuromorphic devices are expected to contribute to the development of neural networks, while research on disposable lab-on-a-chip systems and epidermal electronics is generating novel interaction routes between biological systems, bioelectronics devices, and consumer electronics, such as smartphones and portable devices.
Because of the general involvement of ionic transport in biological environments, organic bioelectronic devices are inherently slow, i.e. characterized by slow switching capabilities, limited to few kHz. This fundamental aspect brings along some limitations and non-idealities, such as low-frequency operation and fluctuations of the operating parameters of the devices. The ultimate goal of the LEAPh project is to develop a Light-modulated organic Electrolyte-gAted Phototransistor. This novel kind of bioelectronic device is specifically devised to address in an unprecedented way the low-operating frequency of current bioelectronics, possibly reaching the MHz regime, as well as providing a noise-free measurement of biochemical and biological interactions. Moreover, the same technology could pave the way towards a new class of low-voltage organic electro-optical systems.
