Friction force microscopy (FFM) is widely used to clarify tribological properties on the micro and nano scale. On the other hand, lubrication at small gaps has attracted increasing attentions along with the recent progress of precision processing technology. When applying FFM to measurement of properties of lubrication at small gaps, gap control between the sliding probe and sample surface is indispensable. In this report, we propose a microprobe capable of controlling the gaps by embedding an electrostatic actuator in the probe.

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The ultimate target of our research is to measure the zero-point motion of microcantilever as a macroscopic object. In order to achieve the target, it is necessary to remove the thermal vibration which is the limit of measurement. Up to now, we have been using the Michelson interferometer for the feedback cooling of the thermal vibration of microcantilever. We decided to use Fabry-Pérot (FP) interferometer which has higher finesse to improve S/N, because the noise level of the detection system determines the limit of suppression of thermal vibration. We construct an FP interferometer with a mirror and a microcantilever which will be used for the measurement of the thermal vibration. We have succeeded in the measurement the thermal vibration of microcantilever and reducing the noise level about hundredfold using FP interferometer.

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Water repellent effect and antifouling effect are related to wettability of the solid surface. There are many methods to value the wettability of droplet on a solid surface, such as lateral observation and interference fringe method with topdown laser. In the case of lateral observation, when the drop is spread to a thin film the shape of liquid droplet can hardly be observed. The top-down interferometry method could observe in the case of the contact angle of a liquid droplet is small. However, any other experimental operations cannot be done above the droplet. In our experiment, the wetting behavior of liquid droplets can be evaluated by calculating the spacing width of interference fringe. And we developed a device to measure the profile of gas-liquid interface by fringe method with bottom up oblique incident light and the gas-liquid interface shape is measured.

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The MPC polymer is biocompatible and is used as a coating material for medical instruments such as artificial joints and stents. And it was reported that the MPC polymer thin film of several tens of nm thick coated on the sliding surface of the artificial joint became a hydrated gel with water in the body and has high lubricity. In this study, simultaneous measurement of rheological properties (shear viscoelasticity) and film deformation is realized for hydrated MPC polymer thin film, and the relationship between both is clarified. We expected our achievements would lead to the development of hydration lubrication that realize both cleanliness and long life in medical and care devices.

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This paper reports observation and analysis of crack propagation on wave-shaped metal tracks on stretchable substrates. Copper tracks with various thicknesses and amplitudes of wave-shapes were fabricated by photolithography on polyurethane substrates. Crack characteristics in the tracks under stretching load of the samples were investigated with respect to elongation at break, crack width, and the number of induced cracks. As result, the elongation when the first break occurs increases with track thickness. The crack width increases with the elongation of the samples at the first break. The gradient of the number of the cracks decreased as the track thickness increased.

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In this paper, we report the vibration control of an artificial cochlear epithelium. The device is a trapezoidal piezoelectric membrane with patterned Al electrodes. The resonance frequency of the piezoelectric membrane varies locally according to the longitudinal position, and the electric potential difference is produced by the vibration of the membrane induced by sound stimuli. In this study, we use the electrodes to apply electrical stimuli to the piezoelectric membrane. When the frequencies of the electric stimuli are the same as those of the sound stimuli, it is found that the amplification/damping of the local membrane vibration is possible by choosing the appropriate phase difference between the electric stimuli and the sound stimuli. This vibration control technique can be applied to the development of the artificial cochlear epithelium with nonlinear response, which is necessary to mimic the wide dynamic range of human cochlea.

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Thermophoresis is the motion of micro/nanoparticles induced by the temperature gradient of fluids. In the present paper, we successfully apply the thermophoretic phenomena to the filtration technique of microparticles in a microfluidic device. A local temperature increase in a microchannel is produced by irradiating the near-infrared laser and the radial temperature profile is measured by the laser-induced florescence. The laser is moderately focused at the inlet of contraction in the microchannel. Since the microparticles are repelled from the hot region, they hardly approach the inlet of contraction. As the result, only the solution passes through the contraction.

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We fabricated a new diaphragm micropump composed of the piezoelectric Pb(Zr,Ti)O₃ (PZT) thin films on the stainless-steel (SS) foil substrates to reduce the driving voltage. To miniaturize and simplify the micropump structure, the diaphragm and microchannel with diffusers were monolithically formed on the 30-μm-thick SS substrates by photolithography and wet etching. We directly deposited the 1-μm-thick PZT thin films on the SS diaphragm by dip coating with a sol-gel solution. To evaluate the driving characteristics of the fabricated micropump, the SS diaphragm was actuated by applying AC voltage to the PZT thin films. The displacement of the 9-μm-thick SS diaphragm was 1.7 μm with 10 V_pp-driving voltage at 1 Hz.

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Deformation behavior of a thin liquid film on a substrate is investigated numerically, where the film is confined by a solid surface across a gas layer. The evolution of the film surface is governed by a thin film equation, in which the disjoining pressure is taken into account. In the geometry, the disjoining pressure includes a term associated with attractive force between the liquid and upper solid surfaces. When the upper surface is not parallel to the substrate surface, the disjoining pressure becomes nonuniform, and then, the film surface becomes unstable. The instability induces protrusion growth on the film surface, and the behavior depends on the in-plane velocity of the substrate.

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Gel-type temperature sensor based on fluoresGenGe polarization measurement of fluoresGent moleGule mixed in gel solution is proposed and desGribed in this study. Gels Gan be applied easily to various surfaGes and shows less effeGts on human skin. By Gombining with optiGal measurement, quiGk and Gonvenient temperature measurement Gan be made. Polarization measurement is a method related to the Gorrelation between rotational Brownian motion of fluoresGent moleGules and temperature. Therefore, droplet volume effeGts showed signifiGantly smaller effeGts on fluoresGenGe polarization degree P Gompared with intensity measurements. Measurement of the surfaGtant GonGentration effeGts on P showed that P inGreases with GonGentration and Gonverges to a Gertain value. This distribution Gould be modeled by Gonsidering the relationship of GonGentration and Gorrelation length of surfaGtant Ghain network. Further, good Gorrelation between gel temperature and P was obtained.

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Non-contact thermal flow sensors have an ability to measure flow rate of various fluids. However, heat transfer around the sensors becomes complicated from conventional contact sensors due to the existence of layers placed between the sensor, heater and fluid. In this study, effects of the size of sensor components and thermophysical properties of the fluid on the heater output were analyzed by the finite element method to develop a non-contact thermal flow sensor model. From the analysis results, we clarified the dimensions of the sensor components and fluid properties must be taken into account to estimate the relationship between the flow rate and heater output.

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Application expansion of Al/Ni multilayer exothermic materials is an important challenge for the future use as a joining heat sources. In this paper, we report characteristics of exothermic pellet shaped by press molding as a function of compounding ratio for binder material and Al/Ni multilayer material.

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This study investigated the interaction between micro-glow corona and organic materials. Micro-glow corona is very small plasma, which is generated on the tip of a needle electrode at atmospheric pressure. In this study, a hollow electrode with an inner dimeter of 4 mm was used as a counter electrode to generate the micro-glow corona. In addition, a small plate electrode was set behind a dielectric material as a sample to keep the micro-glow corona by barrier discharge. AC voltage at 100 Hz was applied to the needle electrode. When the gap distance between the tip of the needle electrode and the dielectric material was changed from approximately 0.5 mm to 10 mm, the discharge current and discharge onset voltage of the micro-glow corona were measured and analyzed. In a small area of the dielectric material surface, denaturation was observed after discharge.

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Engineered metallic nanoparticles can work as effective optical resonators in dielectrics. Such hybrid structures are expected to be used for highly sensitive detection, enhanced luminescence devices and so on. Microstructures of densely assembled nanoparticles were formed by femtosecond laser direct irradiation in liquid. When femtosecond laser is focused into dilute AgNO₃ solution with SiO₂ and Au nanoparticles, cladding layer of densely packed nanoparticles were precipitated around Ag microstructures, which was precipitated by femtosecond laser reduction. Precipitated volume was markedly increased by the assembling of nanoparticles. This novel laser patterning technique is useful for Au nanoparticles buried inside SiO₂ matrix.

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For realizing magnetic MEMS devices, the sub-millimeter pitch multipole magnetization in permanent magnet films having a thickness of several ten micrometers is studied. Both permanent magnet (Pr-Fe-B) and SiOx layers having a thickness of about several ten micrometers were deposited on Si substrates by pulsed laser deposition (PLD). The micro magnetization of the PLD films was realized by weakening the coercive force of the magnet by laser assisted heating.

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Cu-based mesh-thermal detector was fabricated using femtosecond laser reduction patterning on planer glass substrate. First, the width of line patterns formed in various scan speed were evaluated. Then, the lattice structures of the micropatterns formed in scan speed of 5 mm/s, scan pitch of 5 or 25 μm were examined using X-ray diffraction analysis. When the scan pitch was 25 μm, the lattice patterns were Cu-rich materials with the electrical resistivity of 4.1×10^-5 Ωm. Cu₂O-rich patterns with the electrical resistivity of 1.2×10^-1 Ωm were obtained when the scan pitch was 5 μm. Finally, we demonstrated the fabrication of Cu-based mesh-thermal detectors with the scan pitch of 25 μm. The thermal detector provided the plus temperature coefficient of resistance of 0.002/ºC. This mesh patterning technique is useful for fabricating microdevices such as sensors.

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Thermoelectric couples which consisted of p-type and n-type thermoelectric elements were directly written on glass substrates using femtosecond laser reduction of CuO/NiO mixed nanoparticles. CuO/NiO nanoparticle solution including CuO and NiO nanoparticles, ethylene glycol, and polyvinylpyrrolidone, was spin-coated on glass substrates. Then, p-type and n-type thermoelectric elements were formed by raster scanning of focused femtosecond laser pulses. After rinsing the samples into ethylene glycol and ethanol, the thermoelectric couples were fabricated on the substrates. Cu–Ni- and Cu₂O/NiO-rich micropatterns were selectively formed by controlling the laser scanning speed. The Cu–Ni-based and Cu₂O/NiO-based micropatterns exhibited n-type and p-type thermoelectric properties, respectively. An open-circuit voltage of the fabricated thermoelectric couple was 0.25 mV/K which was almost consistent with the estimated values using each Seebeck coefficient of the p-type and n-type thermoelectric elements. This selective direct-writing process of p-type and n-type thermoelectric materials is useful to fabricate various thermoelectric-type sensors.

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This paper reports a mismatch compensation technique for a frequency modulated (FM) / whole angle (WA) gyroscope using independently controlled CW/CCW mode oscillations. The frequency and Q-factor mismatches of a 2-dimensional resonator could be compensated by adjusting X-Y phase and amplitude differences of driving signals. The proposed technique drastically reduced the unwanted periodic frequency fluctuation in the FM-mode operation and the periodic angle error in the WA-mode operation.

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Multiple microholes measuring 12 μm in diameter were formed at the center of a 1.2 μm-thick SiN (silicon nitride) membrane supported by a Si frame. Chemical release through the microholes permits localized stimulation of a cellular tissue that is placed on the SiN membrane. In this study, an agar slice was placed on the SiN membrane instead of a cellular tissue. Then, ultrapure water was released from the microholes instead of stimulant solution, and a flow rate of water passing through the microholes was measured. Also, agar slices were stained with a crystal violet solution which was released from microholes, and the stained areas were evaluated in various flow rates.

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This paper presents a novel culture technique for deriving and separating extracellular vesicles (EVs) from human lymphocytes using chemical stimulation in a microhole array devise. Lymphocytes stained with fluorescent dye DiI were immobilized on the microholes of 4 μm in diameter using cell-anchoring molecules, and stimulated chemically with sodium butyrate (NaB). EVs were derived from the cell membranes located on the microholes because flexibility of the cell membranes increases when oleyl groups of the cell-anchoring molecules are inserted into the membranes. Then, EVs passed through the microholes, which resulted in separation of EVs from lymphocytes. Also, it was found that the distribution of diameter of the obtained EVs had a peak of about 2 μm.

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This manuscript describes selective electrofusion of cell-sized liposomes using microfabricated dielectrophoretic tweezer. We fabricated round-tip dielectrophoretic tweezers by microfabrication techniques. We enabled selective manipulation of liposomes by applying alternate current to the tweezer. As we control the frequency of the current, we attract or repulse the liposomes. Liposomes were selectively manipulated one-by-one and paired by the tweezers. Finally we paired two cell-sized liposomes in a hand-made electrofusion chamber by using the tweezer. The paired liposomes were contact with each other by applying alternate current, then fused by pulses of direct current. We believe our technique will be useful in liposome and cell fusion study for artificial cell research.

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In this paper, we report a microfluidic device for pairing uniformly sized liposomes and fusing the paired liposomes. Our microfluidic device is composed of dynamic micro array for pairing liposomes and three-dimensional electrode for fusing liposomes. Electrodes should be located in proper position of a dynamic micro array for applying sufficient electric field to fuse liposomes. By using low melting point alloy, 3D electrodes were integrated in the dynamic microarray device to fuse the paired liposomes. Two uniformly sized liposomes were successfully paired in the dynamic micro array device and fused by the integrated 3D electrode. We believe that this dynamic micro array device will become a useful microfluidics device for vesicle fusion.

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Cell stimulation device using carbon nanotubes (CNTs) was fabricated for repairing cell damages and promoting cell growth. Vertically aligned CNTs were synthesized on Ti substrate for working electrode. Pt was deposited on polydimethylsiloxane (PDMS) for counter electrode. This device could give electrical stimulation to cells on CNTs. PC12 cells were cultured on Ti or CNTs and with or without electric stimulation. Lengths and number of neurite per cells were measured to investigate the effect of electrical stimulation. CNTs without stimulation demonstrated most promoted cell growth in various conditions. In condition of CNTs with stimulation, Length of neurite was shorter than without stimulation and direction of neurite was most various.

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Regeneration of neuron cells is expected to be applied for the procedure of dementia. For regeneration of neuron cells, stretch mechanical stimulation by devices using vertically aligned carbon nanotubes (CNTs) was developed and the relationship between the strain distribution and cell growth pattern was investigated. Device was made of PDMS and CNTs and stretched with a tensile machine. PC12 was cultured with 0%, 5%, 20% strain with 0.1Hz. Although some previous studies reported the cytotoxicity of CNTs, that cells adhere and grow on CNTs as well. Therefore, CNTs used in this study were found to have cell culture compatibility. The lengths of nerve processes have no differences between static and stretch culture. But there are some huge nerve processes with stretch culture. So possibility of beneficial was suggested with CNTs and stretch culture.

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We proposed a method for observing diffusion of hydrophobic biomolecules in asymmetric lipid bilayer. First, we developed a device for sequentially forming asymmetric lipid bilayers with various combination of asymmetric lipid leaflet by droplet split-and-contact method[1]. This device enables us to exchange a leaflet of lipid bilayer, maintaining membrane asymmetry. Asymmetry of hydrophobic biomolecules in lipid bilayer is broken fast, thus observation of hydrophobic biomolecular diffusion in lipid bilayer was difficult. By using proposed device, however, we can control the time in which the biomolecular diffuse from initial asymmetric state. Therefore, we can evaluate the amount of the diffused biomolecule in various diffusion time. According to this procedure, we obtained the dynamics of hydrophobic biomolecular diffusion in lipid bilayer.

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This paper presents a novel microfluidic device for high throughput ion-channel analysis. To analyze the electrophysiological properties of cells efficiently, we designed the electrically independent microchannels on the microfluidic device. The microfluidic device is composed of a silicon-on-insulator (SOI) layer having the trap holes with 9 or 12 μm diameter, poly-dimethylsiloxane (PDMS) microchannel chips and glass substrate with Pt electrodes. We successfully trapped the multiple cells on one device without damage by applying negative pressure to the microchannels with a syringe pump. Finally, we confirmed that the each trap hole was strongly sealed with the cell by measuring the electrical impedance, which was more than 1 GΩ, namely gigaseal.

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In this study, we evaluated the suction forces of an elliptical micro suction cup array. The three directional suction forces were compared between the elliptical micro suction cup array and a circler micro suction cup array. In the elliptical micro suction cup array, the ratio of the suction force in the long axis direction to the suction force in the short axis direction was different by 1.7 times when the attaching force was 2 N. In contrast, the ratio in the circular micro suction cup array was almost same. It was confirmed that the suction force of the elliptical micro suction cup array changes depending on the direction of the applied force.

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In development of implantable artificial kidney, we aim to maintain long-term dialysis function. In this research, we coated fluorine-doped diamond-like carbon (f-DLC) film on PES membrane in order to improve the long-term usability of dialysis. First, we present the fabrication method of f-DLC-PES membrane concerning to thickness of f-DLC. Second, we conduct the basic hemofiltration (HF) experiment using multi-layered dialysis device through in vitro. This experiment showed that water permeability declined compared to the untreated PES membrane, but wastes removal was kept properly. These results shows that by coating f-DLC on the PES membrane surface, the possibility that the device can be dialyzed inside the body for the long term while maintaining the dialysis ability.

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This paper reports a method of alginate hydrogel module assembly for heterogeneous 3D structure. This assembly was done by connecting alginate gel modules with ‘cationic nanoparticle’ (CNP) solution. The adhesion is caused by the interaction between CNP and the anionic surface of alginate gel modules. We showed that our method can connect alginate gel modules without external stimuli or maleffect to alginate gel modules with human malignant epithelial cells (HeLa). Alginate gel plates were connected with CNPs and its connection was confirmed to be kept under a mechanical stress. As a demonstration, we achieved to make a bundle of microfiber containing HeLa cells. We believe that our method provides a suitable method for fabrication of artificial tissue structures in the field of tissue engineering.

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Cells are the core of regenerative medicine based on iPS cells and cell therapy. These realizations are expected in our society. For the use of cells in medical treatment and regenerative medicine, human and animal cells are processed and cultured. In the initial stage of cell processing, it is required to obtain cells uniform and stable gene expression. In this paper, we propose an optical system for intranuclear deliver. We established an optical system, measured energy, and evaluated the laser energy. With the constructed optical system, a Ti-coated glass substrate was exposed to nano-pulse laser. After the exposure, we observed the surface.

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Much attention has been paid to the exosome which is a small vesicle working as a tool for cell-cell communication in our body. To clarify unexplained phenomena related with the exosome, a smart technique of exosome handling has been strongly demanded to treat such a delicate substance. For resolution of this issue, we used ion-depletion zone for treating bio-substances including exosome without physical loads. We fabricated a prototype device, and demonstrated on the device to form an ion-depletion zone. The repulsive force of ion-depletion zone was visualized by fluorescent imaging of exosomes pushed out from the ion-depletion zone, and it was evaluated by measuring the zone dimension. After the demonstration, the shape and amount of the exosomes were observed by using an atomic force microscope to estimate the effects of the technique on the sample.

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This research offers simple fabrication process of the microchannel resonator by assemblying to measure mass change in flowing liquid. Flowing liquid such as medium is generally flowing with micro/nano particles such as single cell in the microchannel. The fabrication process of this assembled micro-tube resonator is simply combining three different fabrications of a groove part, a micro-tube part, and a glass part, which are fabricated by common micromachining. The evaluated result of this device is shown that the measured mass by injecting the flowing liquid. The consistent change of mass of flowing liquid is observed. The minimum resolution of the device, which is calculated by noise analysis, is in the value of 1.04 pg.

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Automated liquid handling devices are used in biomedical areas to transfer liquids of submicroliter range. Those devices usually transfer liquids by aspirating and dispensing them with reusable probes, which have the pressure of their tips changed by syringes. The probe and the syringes are connected by tubes, and water is the medium used to change pressure at the probe. The probe is washed periodically with the same water used as medium, and when the water temperature differ from the room’s, thermal expansion of the water and the tubes of the handling device occur due to the wash, causing deviation in the volume dispensed. This paper presents a method to estimate and compensate for this thermal expansion. Results showed the method could reduce the deviations in the volume dispensed from ±190 to ±22nL when transferring liquid at temperature differences between water and room within -11 and 9°C.

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It is extremely difficult to remove SU8 from the substrate. Therefore, researchers have investigated oxygen plasma etching and wet ozone as a means of SU8 removal. However, oxygen plasma etching has unpleasant effect of antimony elimination, because antimony contained in SU8 remains on substrate. The other method, wet ozone, is not suitable because of metallic corrosion. We proposed a new SU8 removal method “DI water (H2O) and lithium chloride (LiCl) doped NMP” which promises swelling furtherance of SU8, and NMP doping H2O and LiCl in the appropriate ratio was of demonstrated value in SU8 fine patterns removing

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This paper presents droplet generation experiments using EWOD (Electro wetting on dielectric).EWOD is a technology for manipulating droplets discretely by controlling the surface wettability electrically. Changing the shape of the electrode and the thickness of the spacer, We investigated optimal conditions for the reservoir. When quadrilateral shape is larger than circular shape it is easy to make constriction by deforming the droplet considerably. When the spacer is not the optimum thickness, it cannot be generated. Spacers with a thickness of 0.22 mm are suitable for producing droplets, and bubbles are generated when high voltage is applied. It is desirable to increase the durability of the device.

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In this study, we describes a microfluidic-based colorful reflective display using dyed water droplets as pixel elements. Our display was made of a PDMS sheet with a connected pixel-patterned microchannel. Several types of dyed water droplets and air gaps were sequentially introduced in the microchannel by sucking with a syringe pump to display a multicolor image. We evaluated the stability of minimum continuous number of water and air dots to display images correctly. We demonstrated displaying three-colored dot-matrix reflective images and Colorful letter “A” on microfluidic-based reflective. We believe that our display could be applicable to energy-less and color-changeable displays for future advertising signage or accessories including bags, shoes, or cloths.

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In this paper, we propose a piezoelectric bimorph vibration energy harvester (VEH) with flexible 3D mesh elastic layer for the purpose of improving output power and lowering resonance frequency. Due to high void ratio of the 3D mesh structure, it is possible to lower the bending stiffness of the cantilever, that is, the deflection of the harvester and the strain in the piezoelectric layer increase. As a result of a vibration test, the resonance frequency is 26% lower and the output power is 1.5 times higher than the conventional solid flat plate VEH. Compared with the flat plate VEH, the proposed mesh VEH has 1.3 times larger tip deflection and the total output power is 20.4 μW that is possible to use as a power supply of low-power consumption sensor nodes for WSNs.

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In this study, we make sure that the dielectric constant of polydimethylsiloxane (PDMS) can be decreased by exposing UV light. Furthermore, as one of the applications of this method, we proposed to put this simple method good use to improve an accuracy of sensor. In our previous work, we fabricated a capacitive force sensor for endoscopic palpation which uses a small force sensor mounted onto an endoscope in order to detect tumor by scanning on the tissue surface and we proofed the practicality [1]. However, this device has large error caused by parasitic capacitance. Accordingly, we use PDMS layers exposed UV light as wire part of this device, stacked them and fabricated the sensor successfully which has a small influence of parasitic capacitance.

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This paper describes temperature responsive janus hydrogel micro particles that can encapsulate various materials. Using a centrifuge based microfluidic device we fabricated the micro particles. The micro particles were made from sodium alginate and poly (N-Isopropylacrylamid) (pNIPAM) so they were able to shrink when the temperature rises. We measured the shrinkage ratio of the particles and it was about 0.91. Furthermore we measured the strength of fluorescence of the janus particle and confirmed that it was compartmentalized. We believe that our micro particles could be applied to actuators for soft robots and sustain release of drug for drug delivery system.

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This paper describes a utility of dry micro-needle electrodes in measurement of electroencephalogram (EEG). Usual wet electrodes need abrasion of stratum corneum and pasting of electrolyte paste as preparation of measurement. Therefore, it would be unpleasant for subjects and time-consuming for experimenters. Thereupon, we developed dry micro-needle electrodes which can measure EEG on hairy scalp. The electrodes avoid hair by pillar and penetrate stratum corneum by micro-needles. In our previous research, it has been proven that our electrodes obtain EEG in same quality to wet electrodes. However, our electrodes have not proposed utilities in many fields. For proving the utility, we conducted ERPs measurement, which is commonly used in psychology and medical science, with oddball task. The oddball task was done with 3 phonetic stimulations /itta/, /itte/ and /itta?/. As a result, P300 was extracted from EEG which was evoked by task. Therefore, the utility of electrode in many fields was proved.

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Currently, microbes are utilized in many fields, such as medicine, food and environment and so on. For more application of microbes, we need a new culture system, which can culture target microbes in large quantities at low cost. Thererupon, we propose a culture system using hydrogel microtube. By using microtube, target microbes are maintained in microtube and get only nutrients and oxygen in open environment. However, there are various competing microbes in open environment, so target microbes don't get enough nutrients to increase. For application of this culture system, by using iodine ball we improve to culture target microbes while prevent competing microbes increasing.

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This paper presents an accurate sampling microstructure formed on a strip. We are developing implantable dialysis system in previous studies, still it has no ability to adjust blood ion concentrations. Thus the patients of the system need to constantly check and manage blood ion concentration by oneself, especially potassium ion, which is greatly related to life support. In this study, we fabricated the strip with a well-controlled geometry of slanted and interlocked micropillars using Off-Stoichiometry Thiol-Enes (OSTE). This can hope for accurate quantitative sampling. And the accuracy of the liquid collecting amount was verified in experiments. In this paper, we didn’t get the result that synthetic microfluidic paper is better with accuracy, but could observe the surface tension.

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This paper describes adhesive characteristics of foot pads for insect-inspired wall-climbing robots. Ants can walk on the smooth vertical surfaces using an adhesive organ and secreted viscous fluid. We fabricated three kinds of adhesive pads inspired by the adhesive organ of ants, a CFRP pad, a sponge and a CFRP pad with a water supplying mechanism. Pure water were provided to the pads, and normal and tangential adhesive forces between the pad and a glass surface were measured. The experimental results show that the hydrophilization treated glass pad generates higher adhesive force than the untreated pad, and the pad with water supply mechanism generates long-lasting adhesive force.

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This study focused on a technique called EWOD (Electrowetting on Dielectric), which allows for control of the wettability using electric potential to transport and handle micro droplets. The EWOD devices were applied to chemical analysis systems and micro motors. However, the droplet handling is mostly confined within the devices and the discharging droplets out of devices have not been performed yet. The present study is aimed at developing a discharging device which performs transporting and discharging of the liquid droplets by utilizing the EWOD.

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In this research, we proposed a method to fabricate a PDMS chain-shaped microchannel by using a chain-shaped alginate hydrogel fiber as sacrificial structure. Embedding and dissolving a chain-shaped alginate hydrogel fiber in a PDMS structure, we succeeded in formation of a chain-shaped microchannel. When we infused 2 different colors of ink into this microchannel from 2 inlets, we achieved the control of flow regimes between laminar and vibrated flows according to their flow rates. Therefore, we believe that the chain-shaped alginate hydrogel fiber will be a useful tool for a simple and low-cost preparation of PDMS microchannels with complex shapes.

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Changing the uneven surface allow the water repellency to increase and decrease. The leaf of the lotus is known to form the water-repellent surface by a surface uneven and characteristic. In reference to it, I made the surface which changed surface height, the width of the column, a diameter. I made the water-repellent surface by applying water-repellent medicine to the uneven surface which I made. I drop a water on the surface which I made and observe the water-repellent increase and decrease by measuring a contact angle and a sliding angle. Based on that we make a surface for transporting water drops.

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In this work, we present a monolithic 3D printing process which integrates liquid-state printed components and interconnects with readily available silicon IC chips in all three dimensions, various orientations and multiple printing layers to deliver system-level functionalities. Our process allows for personalization of objects with electronic capabilities through incorporation of various sensing, actuation and circuit functionalities within 3D complex architectures. As an example application, our process can be used to develop physical assisting and therapeutic devices, a form-fitting glove with embedded programmable heater and “earable” device for real-time detection of core body temperature, that need to be tailored to the patient’s needs and body. Such levels of personalization and 3D integration of system-level functionalities into objects, as enabled by our process, are well aligned with the vision of Internet of Things.

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This paper describes about the head fixation instrument of microneedle electrode. In previous research of us, dry microneedle electrode for electroencephalogram(EEG) was developed. This electrode enables us to measure EEG with painless and preparation-less. However, fixation problem is remained. Current fixation steps are avoiding hair by hand and gum band fixing. These are reasons, this electrode does not enable us to completely easy measurement. For getting rid of these problems, head fixation instrument was developed. It is constructed with two parts, hair avoiding and pressing electrode part and hat which hold all of parts. Except springs, screw and hat, all of parts were fabricated with 3D printer. With this instrument, we tried to measure alpha wave under opened and closed condition. As a result of that, the difference of alpha wave power was detected between opened and closed eye condition. Therefore, this device enable us to simple EEG measurement.

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ATP (Adenosine triphosphate) as a proxy of microbial biomass can be quantitatively detected in submarine environments using the in situ ATP analyzer developed in this study. The microfluidic device for a L-L (luciferin-luciferase) bioluminescence assay, the core element of the analysis module, is integrated with the miniature pumping unit and the photometry module. The transparent PMMA microfluidic device has a microchannel for cell lysis and L-L reaction. A heater and a temperature sensor is integrated to the microfluidic device to maintain optimum temperature for L-L reaction. The completed analyzer has been evaluated in a laboratory and deep-sea environments. As a result of deployment of the in situ ATP analyzer using a remotely operated underwater vehicle, the analyzer was successfully operated in the deep-sea environment at the Omuro-Hole and total ATP (the sum of dissolved and particulate form of ATP) concentration was quantified in situ.

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