Piezoelectric Nano-Fibre Based Acoustic Sensors for Artificial Cochlea

Hearing impairment is one of the most common and most influential disabilities worldwide, affecting more than 300 million people. Sensory neural hearing loss (SNHL) occurs when there is irreversible damage to the sensory hair cells and/or the neural cells that connect to them. Most cases of SNHL cannot be surgically nor medically corrected. Many patients have such severe hearing loss that they do not benefit from hearing aids that just amply incoming acoustic signal and thus need a cochlear implant to restore their hearing. Cochlear implants provide the ability to hear spoken language for profoundly deaf children and adults for the first time, resulting in improved speech, language, educational and social outcomes. However the quality of the sound transmitted through current implants is still far beyond the ideal treatment for the entire spectrum that human cochlea can hear.
The proposed project takes a multidisciplinary approach to design and develop a piezo-nanofibre based frequency analyser and transducer device which can potentially be integrated and implanted inside the cochlea, directly exciting the neurons of the auditory nerve. The research programme will develop and integrate a range of scientific and engineering strategies including: (1) Production of high performance piezoelectric nanofibre based on polymer nanocomposites; (2) Development of position-controlled electrospinning technique for fabrication nanofibres with desired alignment and position; (3) Design, fabrication and integration of piezo-nanofibre based multi-channel acoustic devices and actuators; (4) Development of carbon nanocomposite electrodes and understanding of interface between nerve cell derived neurons and electrodes of the devices in vitro.
We will develop the technology and methodology for manufacturing piezo-nanofibres based acoustic devices with a wide range of frequency selectivity and integrated with bio-regenerative nanostructured electrode. The full capacity of the devices will be explored and evaluated in vitro. The fundamental understanding of piezoelectric property of nanocomposite fibres, interface between the nanostructured electrodes and neuron cell/existing neurons of the auditory nerve will be established. Our on-going collaborative team brings best match expertise, resources and facilities to establish a clear pathway to the future generation of piezo-nano-artificial cochlea, that will not only improve quality of life, but also help reduce healthcare expenditure.

The outcomes of this interdisciplinary project will have direct scientific and engineering impact in the areas of materials, manufacture and biomedical device research communities and industries, as well as clinical, social and economical impact.
Industrial impact
The development of piezoelectric nanofibres, conducting carbon nanocomposites, controlled electrospinning techniques, piezo-nano acoustic sensors and devices will also have significant impacts on the materials, manufacture, medical devices and related instrument industries. The success of acoustic sensor development will potentially make future hearing aid devices have better performance with higher biocompatibility, low-power demand or self-powered, revolutionising hearing aid techniques. The materials and electrospinning technique will open new and high-valued nano-fibrous materials and processing technique to industrial manufacture of a wide range of polymer and polymer nanocomposite nanofibres, electrodes, medical devices, tissue engineering scaffolds, wearable devices, personal care products and energy harvest. The controlled electropsinning process will provide a cost-effective processing platform for fabrication of a range of devices for both medical and general engineering applications in the future.
Clinical impact:
The current hearing aid treatment of hearing loss is one of area which has unmet clinical need, but affects a large proportion of the older population. There are also children born with a hearing loss in one or both ears who need high quality and robust cochlear implants. The successful outcome of the project will provide a potential new generation of cochlear implants based on piezo-nanofibre with high performance and prolonged implantation. This will improve listening abilities offered by cochlear implants, and result in improved speech, language, educational and social outcomes for children and normal communication for older people with hearing loss. The cost-effective sensors will allow new cochlea implants to not only improve quality of life, but also help reduce healthcare expenditure. Therefore the key beneficiaries of the project will be patients and the NHS.

Capacity Building of world leading research, skills, training, knowledge economy:
The project will generate huge advances in nanomaterials, engineering, tissue engineering and manufacturing, as well as the fundamental understanding of piezoelectricity of nanofibres and nancomposites, interface between neuron cell/stem cells and nanocomposite electrodes. It will be an excellent opportunity for training functional materials, biomedical engineering, electronic engineers and scientists. The PDRAs and any undergraduate, postgraduate students that contribute to the project will develop key interdisciplinary skills that will be extremely valuable for UK industry and contribute to the knowledge economy and increase the economic competitiveness of the UK.