Periodic Reporting for period 2 - MITICS (Mixed Ionic and electronic Transport In Conjugated polymers for bioelectronicS)
Periodo di rendicontazione: 2022-02-01 al 2023-07-31
Brain computer interfaces (BCIs) is a modern technology that aims to improve quality of life and longevity, addressing the widespread effects of aging populations, including the growth of mental illness and neurological disorders, for example sclerosis, stroke, brain/spinal cord injury, muscular dystrophy. Therefore, BCIs represent a much promising technology for restoring function loss and are used for rehabilitation and entertainment/gaming.
However, the potential of BCIs is strongly hampered by the invasiveness vs. performance trade-off.
MITICS is developing a highly sensitive and biocompatible amplifying transducer platform for less invasive BCIs. We will leverage the Organic Electrochemical Transistor (OECT), a transducer that was recently shown to yield superior recordings of brain activity than electrodes, and dramatically improve its performance through the design of bespoke materials and coupling with high-gain, low-power amplifiers to achieve a paradigm shift in the invasiveness of BCIs. These highly sensitive amplifying transducers will be fabricated using printing processes which should allow custom designs and a strong decrease in fabrication costs. This breakthrough will allow BCIs to increase decoding accuracy and adoption, thus getting this
However, the potential of BCIs is strongly hampered by the invasiveness vs. performance trade-off.
MITICS is developing a highly sensitive and biocompatible amplifying transducer platform for less invasive BCIs. We will leverage the Organic Electrochemical Transistor (OECT), a transducer that was recently shown to yield superior recordings of brain activity than electrodes, and dramatically improve its performance through the design of bespoke materials and coupling with high-gain, low-power amplifiers to achieve a paradigm shift in the invasiveness of BCIs. These highly sensitive amplifying transducers will be fabricated using printing processes which should allow custom designs and a strong decrease in fabrication costs. This breakthrough will allow BCIs to increase decoding accuracy and adoption, thus getting this
Within the first 30 months of the MITICS (964677), the project consortium has developed new linear semiconductor organic mixed ionic-electronic conductors (OMIEC)s with performance metrics matching existing benchmark materials. We have also developed new small-molecule OMIECs for both blend and single-component OECT work with promising initial results. Working towards more challenging higher-dimensionality architectures, we have developed a new electropolymerisation protocol that affords microporous polymers with tuneable porosity thereby opening up the possibility of tuning electronic and ionic transport pathways independently of each other. A new concept for ambipolar OECTs materials was suggested.
All-atom modeling work has also been performed to understand the ion uptake in the ON and OFF states of p- and n-type semiconductors. We have a developed a computational framework to model: (i) the changes in the structural organization of semiconducting polymer thin films in presence of an electrolyte solution and upon oxidation/reduction of the polymer chains; (ii) the evolution of the electrical conductivity with increasing electrochemical doping.
we have continued to develop and used sophisticated spectroscopic tools to investigate the electrochemical reactions in OECTs. Those include time-resolved spectro-electrochemistry, electrochemical terahertz conductivity, electrochemical Raman and interfacial Sum-Frequency-Generation (SFG) measurements, etc. The morphology of porous organic mixed conductor films was imaged. The electrochemical properties of new conjugated oligomer mixed conductors were studied. Temporal and spatial analysis of mixed conductivity in blend based OECTs were carried out. We have elucidated how backbone structure, side chain polarity, morphology, material blending, porosity and chain alignment affect the electrical and ionic processes in the devices.
Both p-type and n-type OECTs were developed and utilized to create complementary amplifiers with high gain and low power consumption. These devices were integrated into novel circuities and unitized for event-bases sensing.
In parallel, the consortium has worked with the development of all-printed OECTs operating in accumulation mode, to eventually simplify the design and manufacturing of complementary logic circuits. So far, successful results have been obtained for a p-type semiconducting polymer developed in the project. Similar development work to obtain all-printed n-type OECTs operating in accumulation mode is now in progress. Investigations on how different printing conditions affect the OECT switching performances have also been performed.
Next, a freely behaving rat model for validating cortical and implantable electrophysiology devices in the central and peripheral nervous system have been developed. It is used to validate both electrodes and transistors, in both recording and stimulation applications. Flexible circuits were tested, outperforming devices with external electronics. A platform has been developed separating ionic and electronic transport phenomena in doped and intrinsic organic semiconductors and the first example of hole-limited electrochemical doping was demonstrated.
Finally, the testbed development phase to validate MITICS technology for scalp EEG recordings is now completed. This includes the hardware integration of the developed amplification layer as well as the processing pipeline to compare with state-of-the-art systems.
A participation in the EIC T2M Venture Building Programme allows MITICS to explore the possibility of exploiting the OECT manufacturing platform.
All-atom modeling work has also been performed to understand the ion uptake in the ON and OFF states of p- and n-type semiconductors. We have a developed a computational framework to model: (i) the changes in the structural organization of semiconducting polymer thin films in presence of an electrolyte solution and upon oxidation/reduction of the polymer chains; (ii) the evolution of the electrical conductivity with increasing electrochemical doping.
we have continued to develop and used sophisticated spectroscopic tools to investigate the electrochemical reactions in OECTs. Those include time-resolved spectro-electrochemistry, electrochemical terahertz conductivity, electrochemical Raman and interfacial Sum-Frequency-Generation (SFG) measurements, etc. The morphology of porous organic mixed conductor films was imaged. The electrochemical properties of new conjugated oligomer mixed conductors were studied. Temporal and spatial analysis of mixed conductivity in blend based OECTs were carried out. We have elucidated how backbone structure, side chain polarity, morphology, material blending, porosity and chain alignment affect the electrical and ionic processes in the devices.
Both p-type and n-type OECTs were developed and utilized to create complementary amplifiers with high gain and low power consumption. These devices were integrated into novel circuities and unitized for event-bases sensing.
In parallel, the consortium has worked with the development of all-printed OECTs operating in accumulation mode, to eventually simplify the design and manufacturing of complementary logic circuits. So far, successful results have been obtained for a p-type semiconducting polymer developed in the project. Similar development work to obtain all-printed n-type OECTs operating in accumulation mode is now in progress. Investigations on how different printing conditions affect the OECT switching performances have also been performed.
Next, a freely behaving rat model for validating cortical and implantable electrophysiology devices in the central and peripheral nervous system have been developed. It is used to validate both electrodes and transistors, in both recording and stimulation applications. Flexible circuits were tested, outperforming devices with external electronics. A platform has been developed separating ionic and electronic transport phenomena in doped and intrinsic organic semiconductors and the first example of hole-limited electrochemical doping was demonstrated.
Finally, the testbed development phase to validate MITICS technology for scalp EEG recordings is now completed. This includes the hardware integration of the developed amplification layer as well as the processing pipeline to compare with state-of-the-art systems.
A participation in the EIC T2M Venture Building Programme allows MITICS to explore the possibility of exploiting the OECT manufacturing platform.
The interfacing of living systems with modern microelectronics is an aspirational endeavour with wide impacts for healthcare. The full potential of organic materials in bioelectronics has not yet been achieved, because this is a fragmented field with limited work by chemists, physicists and material scientists that appeals to biologists and physicians. MITICS will provide a unique opportunity to bridge these worlds in addressing the shared, well-defined and timely goal of designing and integrating innovative transducer materials for OECT-based brain computer interfaces and their validation and benchmarking. Leaning on the results of this project, this new and essential source of information will have direct beneficial impact on our society, especially for our most fragile and dependent disabled people. One very important purpose of brain computer interface market is to help the people with special disabilities to communicate with others as well as external environments.