Culturing Neurons on MEMS Fabricated P(VDF-TrFE) Films for Implantable Artificial Cochlea

Shintaku, Hirofumi; Tateno, Toshitake; Tsuchioka, Nobuyoshi; Tanujaya, Harto; Nakagawa, Takayuki; Ito, Juichi

doi:10.1299/jbse.5.229

Cited by 16 publications

(16 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…FTIR spectra of electrospun samples show that the crystallization of the polymer occurs in the ferroelectric phase ( figure 7b) due to the presence of the absorption band at 840 cm -1 , characteristic of this phase and the absence of absorption modes of the -phase of PVDF that occur at 855, 795 and 766 cm -1 ) or -phase (833, 812 and P(VDF-TrFE) is therefore obtained by electrospinning in the electroactive phase, showing a large potential for biomedical and tissue engineering applications, especially for bone repair [30], nerve guidance [31,32] or even cochlea reconstruction [33].…”

Section: Resultsmentioning

confidence: 99%

Fiber average size and distribution dependence on the electrospinning parameters of poly(vinylidene fluoride–trifluoroethylene) membranes for biomedical applications

et al. 2012

View full text Add to dashboard Cite

Poly(vinylidene fluoride-trifluoethylene), P(VDF-TrFE), electrospun membranes were obtained from a mixture of dimethylformamide (DMF) and methylethylketone (MEK) solvents. The inclusion of MEK to the solvent system promotes a faster solvent evaporation allowing complete polymer crystallization during the jet travelling between the tip and the grounded collector.The main electrospinning processing parameters were systematically changed to study their influence on fiber dimensions and distribution. Applied voltage and inner needle diameter do not have large influence on the electrospun fiber average diameter but in the fiber diameter distribution. On the other hand, increasing the distance between the needle tip and the collector gives origin to fibers with larger average diameter. Independently on the processing conditions, all mats are produced in the electroactive phase of the polymer. Further, MC-3T3-E1cell adhesion is not inhibited by the fiber mats preparation, showing their potential use for biomedical applications.

show abstract

Section: Resultsmentioning

confidence: 99%

Fiber average size and distribution dependence on the electrospinning parameters of poly(vinylidene fluoride–trifluoroethylene) membranes for biomedical applications

et al. 2012

View full text Add to dashboard Cite

show abstract

“…The vibrations induced by sound and electrical stimuli are expected to be superposed. The piezoelectric material used in this study is a polyvinylidene difluoride (PVDF), because PVDF is biologically compatible [ 8 ]. We describe the fabrication method and details of the device in the following.…”

Section: Experimental Methodsmentioning

confidence: 99%

“…To remove such burdens on patients and to increase patients’ quality of life, a self-contained artificial cochlea has been proposed by one of the authors and their colleagues [ 1 , 2 , 3 ]. Recent advances in the fabrication technologies of micro-electro-mechanical systems have allowed the development of an artificial cochlear epithelium without an external power supply [ 1 , 2 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 ]. Electrical signals in these devices are generated by the deformation of a trapezoidal piezoelectric membrane induced by sound stimuli.…”

Section: Introductionmentioning

confidence: 99%

Artificial Cochlear Sensory Epithelium with Functions of Outer Hair Cells Mimicked Using Feedback Electrical Stimuli

2018

Self Cite

View full text Add to dashboard Cite

We report a novel vibration control technique of an artificial auditory cochlear epithelium that mimics the function of outer hair cells in the organ of Corti. The proposed piezoelectric and trapezoidal membrane not only has the acoustic/electric conversion and frequency selectivity of the previous device developed mainly by one of the authors and colleagues, but also has a function to control local vibration according to sound stimuli. Vibration control is achieved by applying local electrical stimuli to patterned electrodes on an epithelium made using micro-electro-mechanical system technology. By choosing appropriate phase differences between sound and electrical stimuli, it is shown that it is possible to both amplify and dampen membrane vibration, realizing better control of the response of the artificial cochlea. To be more specific, amplification and damping are achieved when the phase difference between the membrane vibration by sound stimuli and electrical stimuli is zero and π, respectively. We also demonstrate that the developed control system responds automatically to a change in sound frequency. The proposed technique can be applied to mimic the nonlinear response of the outer hair cells in a cochlea, and to realize a high-quality human auditory system.

show abstract

“…An implantable device for examining the transmission of sound from the external auditory canal to the piezoelectric membrane was fabricated using a P(VDF-TrFE) membrane (KF-W#2200; Kureha) and a silicon frame according to the methods described previously (31). The surface of the 300-μm-thick silicon substrate (100) was penetrated by hexamethyldisilazane (Tokyo Ohka Kogyo) to enhance adhesion of the P(VDF-TrFE) membrane.…”

Section: Implantable Miniaturizedmentioning

confidence: 99%

Piezoelectric materials mimic the function of the cochlear sensory epithelium

Inaoka

Shintaku²,

Nakagawa³

et al. 2011

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

120

127

View full text Add to dashboard Cite

Cochlear hair cells convert sound vibration into electrical potential, and loss of these cells diminishes auditory function. In response to mechanical stimuli, piezoelectric materials generate electricity, suggesting that they could be used in place of hair cells to create an artificial cochlear epithelium. Here, we report that a piezoelectric membrane generated electrical potentials in response to sound stimuli that were able to induce auditory brainstem responses in deafened guinea pigs, indicating its capacity to mimic basilar membrane function. In addition, sound stimuli were transmitted through the external auditory canal to a piezoelectric membrane implanted in the cochlea, inducing it to vibrate. The application of sound to the middle ear ossicle induced voltage output from the implanted piezoelectric membrane. These findings establish the fundamental principles for the development of hearing devices using piezoelectric materials, although there are many problems to be overcome before practical application.cochlear implant | hearing loss | mechanoelectrical transduction | traveling wave | regeneration T he cochlea is responsible for auditory signal transduction in the auditory system. It responds to sound-induced vibrations and converts these mechanical signals into electrical impulses, which stimulate the auditory primary neurons. The human cochlea operates over a three-decade frequency band from 20 Hz to 20 kHz, covers a 120-dB dynamic range, and can distinguish tones that differ by <0.5% in frequency (1). It is relatively small, occupying a volume of <1 cm 3 , and it requires ∼14 μW power to function (2). The mammalian ear is composed of three parts: the outer, middle, and inner ears (Fig. 1A) (3). The outer ear collects sound and funnels it through the external auditory canal to the tympanic membrane. The cochlea consists of three compartments: scala vestibuli and scala tympani, which are filled with perilymph fluid, and scala media, which is filled with endolymph fluid (Fig. 1C). The scala vestibuli and scala tympani form a continuous duct that opens onto the middle ear through the oval and round windows. The stapes, an ossicle in the middle ear, is directly coupled to the oval window. Sound vibration is transmitted from the ossicles to the cochlear fluids through the oval window as a pressure wave that travels from the base to the apex of the scala vestibuli through the scala tympani and finally to the round window (Fig. 1B). The scala media are membranous ducts that are separated from the scala vestibuli by Reissner's membrane and separated from the scala tympani by the basilar membrane. The pressure wave propagated by the vibration of the stapes footplate causes oscillatory motion of the basilar membrane, where the organ of Corti is located. The organ of Corti contains the sensory cells of the auditory system; they are known as hair cells, because tufts of stereocilia protrude from their apical surfaces (Fig. 1D). The oscillatory motion of the basilar membrane results in the shear motion of the st...

show abstract

Culturing Neurons on MEMS Fabricated P(VDF-TrFE) Films for Implantable Artificial Cochlea

Cited by 16 publications

References 13 publications

Fiber average size and distribution dependence on the electrospinning parameters of poly(vinylidene fluoride–trifluoroethylene) membranes for biomedical applications

Fiber average size and distribution dependence on the electrospinning parameters of poly(vinylidene fluoride–trifluoroethylene) membranes for biomedical applications

Artificial Cochlear Sensory Epithelium with Functions of Outer Hair Cells Mimicked Using Feedback Electrical Stimuli

Piezoelectric materials mimic the function of the cochlear sensory epithelium

Contact Info

Product

Resources

About