ENOBIO dry electrophysiology electrode; first human trial plus wireless electrode system.
ABSTRACT This paper presents the results of the first human trials with the ENOBIO electrophysiology electrode prototype plus the initial results of a new wireless prototype with flexible electrodes based on the same platform. The results indicate that a dry active electrode that employs a CNT array as the electrode interface can perform on a par with traditional "wet" electrodes for the recording of EEG, ECG, EOG and EMG. We also demonstrate a new platform combining wireless technology plus flexible electrodes for improved comfort for applications that take advantage of the dry electrode concept.
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ABSTRACT: In the recording of biomedical signals, a significant noise component is introduced by the electrode. The magnitude of this noise is considerably higher than the equivalent thermal noise from the electrode impedance. As the noise in surface electrodes limits the resolution of biopotential recordings, it is important to understand its origin. It was found that the noise mainly originates in the electrolyte-skin interface and that it is highly dependent on the electrode gel used and the skin properties of the test subject. Depending on skin treatment, magnitudes between 1 and 20 microVrms were measured among subjects. When the metal-electrolyte interface was allowed time to stabilise, electrodes of different metals measured face to face all showed a negligibly small noise magnitude (< 1 microVrms). In pre-gelled electrodes, where the metal-electrolyte interface has stabilised, no difference in noise properties was found between Ag-AgCl electrodes and other metals when measured on the skin. In subjects at rest, the contribution of EMG signals to the total noise level was shown to be negligibly small compared with the noise contribution of the electrolyte-skin interface. The magnitude of the noise of electrodes appeared to be inversely proportional to the square root of the area of the electrode on the skin.Medical & Biological Engineering & Computing 06/2002; 40(3):332-8. · 1.79 Impact Factor
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ABSTRACT: Free-standing aligned carbon nanotubes have previously been grown above 700 degreesC on mesoporous silica embedded with iron nanoparticles. Here, carbon nanotubes aligned over areas up to several square centimeters were grown on nickel-coated glass below 666 degreesC by plasma-enhanced hot filament chemical vapor deposition. Acetylene gas was used as the carbon source and ammonia gas was used as a catalyst and dilution gas. Nanotubes with controllable diameters from 20 to 400 nanometers and lengths from 0. 1 to 50 micrometers were obtained. Using this method, large panels of aligned carbon nanotubes can be made under conditions that are suitable for device fabrication.Science 12/1998; 282(5391):1105-7. · 31.20 Impact Factor
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ABSTRACT: We estimate the stiffness of single-walled carbon nanotubes by observing their freestanding room-temperature vibrations in a transmission electron microscope. The nanotube dimensions and vibration amplitude are measured from electron micrographs, and it is assumed that the vibration modes are driven stochastically and are those of a clamped cantilever. Micrographs of 27 nanotubes in the diameter range 1.0–1.5 nm were measured to yield an average Young’s modulus of 〈Y〉=1.25 TPa. This value is consistent with previous measurements for multiwalled nanotubes, and is higher than the currently accepted value of the in-plane modulus of graphite.Physical Review B 11/1998; 58(20). · 3.77 Impact Factor