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A comprehensive review of the electroactive materials for non-enzymatic glucose sensing and sensing devices has been performed in this work. A general introduction for glucose sensing, a facile electrochemical technique for glucose detection, and explanations of fundamental mechanisms for the electro-oxidation of glucose via the electrochemical technique are conducted. The glucose sensing materials are classified into five major systems: (1) mono-metallic materials, (2) bi-metallic materials, (3) metallic-oxide compounds, (4) metallic-hydroxide materials, and (5) metal-metal derivatives. The performances of various systems within this decade have been compared and explained in terms of sensitivity, linear regime, the limit of detection (LOD), and detection potentials. Some promising materials and practicable methodologies for the further developments of glucose sensors have been proposed. Firstly, the atomic deposition of alloys is expected to enhance the selectivity, which is considered to be lacking in non-enzymatic glucose sensing. Secondly, by using the modification of the hydrophilicity of the metallic-oxides, a promoted current response from the electro-oxidation of glucose is expected. Lastly, by taking the advantage of the redistribution phenomenon of the oxide particles, the usage of the noble metals is foreseen to be reduced.
Wan-Ting Chiu; Tso-Fu Chang; Masato Sone; Hideki Hosoda; Agnès Tixier-Mita; Hiroshi Toshiyoshi. Developments of the Electroactive Materials for Non-Enzymatic Glucose Sensing and Their Mechanisms. Electrochem 2021, 2, 347 -389.
AMA StyleWan-Ting Chiu, Tso-Fu Chang, Masato Sone, Hideki Hosoda, Agnès Tixier-Mita, Hiroshi Toshiyoshi. Developments of the Electroactive Materials for Non-Enzymatic Glucose Sensing and Their Mechanisms. Electrochem. 2021; 2 (2):347-389.
Chicago/Turabian StyleWan-Ting Chiu; Tso-Fu Chang; Masato Sone; Hideki Hosoda; Agnès Tixier-Mita; Hiroshi Toshiyoshi. 2021. "Developments of the Electroactive Materials for Non-Enzymatic Glucose Sensing and Their Mechanisms." Electrochem 2, no. 2: 347-389.
An extended version of cross-bar type addressing technique is developed for three-port electrostatic micro shutters arranged in an arrayed format. A microelectromechanical systems (MEMS) shutter blade suspended by a pair of torsion beams works as a movable electrode that is either attracted upwards to the cover plate to close the aperture or retracted downwards into the through-hole to open it. Tri-state positioning of the shutter—i.e., open, rest, and close—is controlled by the hysteresis loop of the electrostatic pull-in and release behavior using the combination of the voltages applied to the shutter, the cover, and the substrate. Random access addressing of the shutters is demonstrated by a control system composed of MATLAB-coded Arduino electronics. The shutter array developed in this work is for a sub-cluster of a reconfigurable shutter array under development for a multi-object galactic astronomy.
Xufeng Liu; Takuya Takahashi; Masahiro Konishi; Kentaro Motohara; Hiroshi Toshiyoshi. Random Access Addressing of MEMS Electrostatic Shutter Array for Multi-Object Astronomical Spectroscopy. Micromachines 2020, 11, 782 .
AMA StyleXufeng Liu, Takuya Takahashi, Masahiro Konishi, Kentaro Motohara, Hiroshi Toshiyoshi. Random Access Addressing of MEMS Electrostatic Shutter Array for Multi-Object Astronomical Spectroscopy. Micromachines. 2020; 11 (8):782.
Chicago/Turabian StyleXufeng Liu; Takuya Takahashi; Masahiro Konishi; Kentaro Motohara; Hiroshi Toshiyoshi. 2020. "Random Access Addressing of MEMS Electrostatic Shutter Array for Multi-Object Astronomical Spectroscopy." Micromachines 11, no. 8: 782.
Despite the development of energy-efficient devices in various applications, microelectromechanical system (MEMS) electrostatic actuators yet require high voltages to generate large displacements. In this respect, electrets exhibiting quasi-permanent electrical charges allow large fixed voltages to be integrated directly within electrode structures to reduce or eliminate the need of DC bias electronics. For verification, a −40 V biased electret layer was fabricated at the inner surface of a silicon on insulator (SOI) structure facing a 2 μm gap owing to the high compatibility of silicon micromachining and the potassium-ion-electret fabrication method. A −10 V electret-augmented actuator with an out-of-plane motion membrane reached a sound pressure level (SPL) of 50 dB maximum with AC input voltage of Vin=5 Vpp alone, indicating a potential for acoustic transducer usage such as microspeakers. Such devices with electret biasing require only the input signal voltage, thus contributing to reducing the overall power consumption of the device system.
Chikako Sano; Manabu Ataka; Gen Hashiguchi; Hiroshi Toshiyoshi. An Electret-Augmented Low-Voltage MEMS Electrostatic Out-of-Plane Actuator for Acoustic Transducer Applications. Micromachines 2020, 11, 267 .
AMA StyleChikako Sano, Manabu Ataka, Gen Hashiguchi, Hiroshi Toshiyoshi. An Electret-Augmented Low-Voltage MEMS Electrostatic Out-of-Plane Actuator for Acoustic Transducer Applications. Micromachines. 2020; 11 (3):267.
Chicago/Turabian StyleChikako Sano; Manabu Ataka; Gen Hashiguchi; Hiroshi Toshiyoshi. 2020. "An Electret-Augmented Low-Voltage MEMS Electrostatic Out-of-Plane Actuator for Acoustic Transducer Applications." Micromachines 11, no. 3: 267.
We have developed a micro-electro-mechanical systems (MEMS) electrostatic vibratory power generator with over 100 μWRMS of (root-mean-square) output electric power under 0.03 GRMS (G: the acceleration of gravity) accelerations. The device is made of a silicon-on-insulator (SOI) wafer and is fabricated by silicon micromachining technology. An electret built-in potential is given to the device by electrothermal polarization in silicon oxide using potassium ions. The force factor, which is defined by a proportional coefficient of the output current with respect to the vibration velocity, is 2.34 × 10−4 C/m; this large value allows the developed vibration power generator to have a very high power efficiency of 80.7%. We have also demonstrated a charging experiment by using an environmental acceleration waveform with an average amplitude of about 0.03 GRMS taken at a viaduct of a highway, and we obtained 4.8 mJ of electric energy stored in a 44 μF capacitor in 90 min.
Hideaki Koga; Hiroyuki Mitsuya; Hiroaki Honma; Hiroyuki Fujita; Hiroshi Toshiyoshi; Gen Hashiguchi. Development of a Cantilever-Type Electrostatic Energy Harvester and Its Charging Characteristics on a Highway Viaduct. Micromachines 2017, 8, 293 .
AMA StyleHideaki Koga, Hiroyuki Mitsuya, Hiroaki Honma, Hiroyuki Fujita, Hiroshi Toshiyoshi, Gen Hashiguchi. Development of a Cantilever-Type Electrostatic Energy Harvester and Its Charging Characteristics on a Highway Viaduct. Micromachines. 2017; 8 (10):293.
Chicago/Turabian StyleHideaki Koga; Hiroyuki Mitsuya; Hiroaki Honma; Hiroyuki Fujita; Hiroshi Toshiyoshi; Gen Hashiguchi. 2017. "Development of a Cantilever-Type Electrostatic Energy Harvester and Its Charging Characteristics on a Highway Viaduct." Micromachines 8, no. 10: 293.
Setting a target on implantable medical devices such as respiration-supporting pacemaker for amyotrophic lateral sclerosis (ALS), we develop an energy harvester that could earn electrical power from the mechanical motion of liquid droplets on an electrical charged plate called “electret.” A PDMS sheet with micro fluidic channels is laminated onto a silicon substrate with built-in permanent electrical charges. A pair of capacitive electrodes is formed in the sealed fluidic channels, in which water droplets are displaced back and forth due to the applied pressure that simulates the motion of heartbeat. Typical output power of 0.17 µW/cm2 is obtained at 0.47 Hz. Analytical model suggests that the extension of the electret plate to ~ 6 cm2 delivers 1 mW power, which is sufficient to drive the implantable medical devices.
Hiroshi Toshiyoshi. A Liquid-driven MEMS Vibrational Energy Harvester. Proceedings of The 7th International Multidisciplinary Conference on Optofluidics 2017 2017, 1 .
AMA StyleHiroshi Toshiyoshi. A Liquid-driven MEMS Vibrational Energy Harvester. Proceedings of The 7th International Multidisciplinary Conference on Optofluidics 2017. 2017; ():1.
Chicago/Turabian StyleHiroshi Toshiyoshi. 2017. "A Liquid-driven MEMS Vibrational Energy Harvester." Proceedings of The 7th International Multidisciplinary Conference on Optofluidics 2017 , no. : 1.
We propose a micromachined XY stage consisting of eight ‘L’ shaped (spider-leg) stage-suspension springs and rotational comb-drive actuators for two-dimensional microlens scanner. The new design features rotational comb drives that are attached to the rotational hinge, where the movement of the comb drive is constrained to rotation only. The mechanism ensures stable and satisfactory in-plane motion. We designed a microlens-type optical scanner utilizing the spider-leg actuator. Silicon was used as a lens material because it is mechanically stable and optically transparent to infrared light around the wavelength of 1.55 μm. The microlens scanner was fabricated by lens-profile-transferring to the structural layer of a silicon on insulator (SOI) wafer by the reactive ion etching (RIE) from thermally reflowed photo resist (PR) and continuing two deep RIEs. The XY stage moved more than 55 μm independently in the X and Y directions with applied voltage of 40 V. The optical coupling loss between the faced microlens-pair showed 10.5 dB with microlenses of a 1 mm diameter, which can be applied to the optical cross connect (OXC).
Ho Nam Kwon; Jong-Hyun Lee; Kazuhiro Takahashi; Hiroshi Toshiyoshi. MicroXY stages with spider-leg actuators for two-dimensional optical scanning. Sensors and Actuators A: Physical 2006, 130-131, 468 -477.
AMA StyleHo Nam Kwon, Jong-Hyun Lee, Kazuhiro Takahashi, Hiroshi Toshiyoshi. MicroXY stages with spider-leg actuators for two-dimensional optical scanning. Sensors and Actuators A: Physical. 2006; 130-131 ():468-477.
Chicago/Turabian StyleHo Nam Kwon; Jong-Hyun Lee; Kazuhiro Takahashi; Hiroshi Toshiyoshi. 2006. "MicroXY stages with spider-leg actuators for two-dimensional optical scanning." Sensors and Actuators A: Physical 130-131, no. : 468-477.