研究者詳細 - 尾上　弘晃

論文 - 尾上　弘晃

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One-Step Fabrication of Multi-Functional Core-Shell Janus Microparticles for Theranostics Application

Tsuchiya M., Kurashina Y., Heo Y.J., Onoe H.

Proceedings of the IEEE International Conference on Micro Electro Mechanical Systems (MEMS) （Proceedings of the IEEE International Conference on Micro Electro Mechanical Systems (MEMS)） 2020-January 32 - 35 2020年01月

ISSN 9781728135809

© 2020 IEEE. We present a one-step method to fabricate microparticles to detect substances and release drugs in our bodies. Our microparticles have two compartments and an outer shell. The two compartments (Janus cores) enable the encapsulation of different materials separately for diagnosis and therapy while the outer shell reduces the adhesion and protects the encapsulated materials. These multi-functional core-shell Janus microparticles are fabricated by simply ejecting pre-gel solutions into a calcium chloride solution under centrifugal gravity application and UV irradiation. Moreover, we implanted these microparticles in biological tissue and demonstrated the transdermal sensing and drug model release. We believe that our fabrication method and particle design could be an effective approach for multi-functional smart theranostic medicine.

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Microfluidic Reflective Display with Primary Color Sub-Pixels

Muramatsu J., Onoe H.

ISSN 9781728135809

© 2020 IEEE. This paper describes a multi-color microfluidic reflective display with sub-pixels. Our display is composed of four independent three-dimensional (3D) PDMS microchannels where CMYK (Cyan, Magenta, Yellow, Key plate) ink droplets are spatially positioned as CMYK sub-pixels. By combining CMYK sub-pixel colors, our device displays multiple colors on a single pixel. We evaluated the optical characteristics of each CMYK sub-pixels and confirmed that multi-colors can be displayed by adjusting the combination of sub-pixel colors. We believe that our display could be applied to next-generation wearable displays and sign boards as a low-energy consumption, flexible and full-color reflective display.

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Locally Bendable Stimuli-Responsive Hydrogel Actuator with Axially Patterned Functional Materials

Takeuchi N., Nakajima S., Kawano R., Hori Y., Onoe H.

ISSN 9781728135809

© 2020 IEEE. This paper describes a locally bendable stimuli-responsive hydrogel actuator with axially patterned functional materials fabricated by a valve-controlled microfluidic device. By application of an external stimuli to the complete actuator, it can be locally bended owing to the axial pattern of the responsive and non-responsive material. These materials are axially patterned on a microfiber through the Y-shaped channel coupled with the open/close motion of the valves in the microfluidic device. The microfluidic device can regulate the on/off of the flow by thin membrane pneumatic valves controlled by a computer. The patterning frequency of the two materials in the microfiber could be adjusted by modifying the switching intervals of the solutions. Also, we successfully demonstrated the curvature-change through heating and cooling. We believe that this locally bendable stimuli-responsive hydrogel could contribute to microfiber-shaped soft actuators, biomedical sensors, and self-assembly of complex 3D microstructures.

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Microfluidic-based multicolor reflective display using water/air microdroplet trains

Kobayashi K., Onoe H.

21st International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2017 （21st International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2017） 744 - 745 2020年

ISSN 9780692941836

© 17CBMS-0001. This paper describes a microfluidic-based multicolor reflective display using dyed water droplets as pixel elements. Our display was composed of a PDMS sheet with a connected pixel-patterned microchannel. Several types of water droplets and air gaps were sequentially introduced in the microchannel by sucking with a syringe pump to display . 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. 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.

Graphene-based inline pressure sensor integrated with elastic microfluidic tube

Inoue N., Onoe H.

ISSN 9780692941836

© 17CBMS-0001. This paper describes a poly-dimethylsiloxane (PDMS) microfluidic tube integrated with graphene sheets for an inline flow pressure sensor. The PDMS tube was fabricated by molding and a graphene sheet was transferred on the surface of the PDMS tube. Pressure caused by fluid flow inside the tube was monitored by changes in the electric resistance of the transferred graphene. Our pressure sensor could be suitable for precise pressure measurement of small amount of fluid in microfluidic systems including organ-on-a-chip devices.

Double-layer collagen microtube for perfusable heterogeneous culture

Itai S., Onoe H.

ISSN 9780692941836

© 17CBMS-0001. We present a double-layer collagen microtube device for in vitro perfusable multilayered 3D cell culture. Thicknesses of the collagen layers in the microtube can flexibly designed, and heterogeneous types of cells can be co-cultured in each collagen layer or surfaces. Moreover, while our collagen tube is directly attached to silicone tubes, the collagen microtube can be easily connected to an external pump system for perfusion culture. We believe that our device could help easy fabrication of various tissue models mimicking in vivo, especially blood vessel models or vascularized skin models, and contribute to the development of pharmacokinetic testing platforms and regenerative medicine.

Actomyosin-collagen hybrid soft actuator

Kohno K., Kwara S., Hiratsuka Y., Onoe H.

MicroTAS 2020 - 24th International Conference on Miniaturized Systems for Chemistry and Life Sciences （MicroTAS 2020 - 24th International Conference on Miniaturized Systems for Chemistry and Life Sciences） 997 - 998 2020年

ISSN 9781733419017

Soft actuators mimicking biological muscles have been built by polymerizing actin and myosin in vitro to construct actomyosin, however, the mechanical strength of the actomyosin was generally not sufficient for practical uses as an actuator. In this study, we proposed an actomyosin-collagen hybrid actuator with high mechanical strength and formability by reconstructing actomyosin biomolecular linear motors inside collagen gel matrix. This actuator can be contracted by adding ATP and returned to its original length by applying an external tensile force, resulting that the actuator could be driven multiple times. This actuator could be expected as an actuator for environment-friendly micro-robots and wearable medical devices.

Wireless and battery-free digestible sensor for intestinal bacteria monitoring

Inami A., Iyama E., Itai S., Onoe H.

ISSN 9781733419017

We propose a wireless and battery-free digestible sensor for the detection of intestinal bacteria. This device has a dissolvable Mg planer coil that is covered with a coating layer composed of dietary fiber. This dietary fiber layer is selectively degraded by intestinal bacteria, resulting in the dissolution of the Mg coil that can be wirelessly monitored without any internal batteries. In this report, in vitro wireless detection on the degradation of our device was demonstrated as a proof-of-concept experiment. We believe that this device could be a new non-toxic easy-monitoring device for detecting biological substances without heavy burden to human.

Stimuli-responsive hydrogels embedding mechanichal metamaterials for high sensitive biochemical sensors

Yamawaki S., Tsuchiya M., Onoe H.

ISSN 9781733419017

This paper describes a novel approach to magnify the shrink/swell degree of stimuli-responsive hydrogels with micro-scale mechanical metamaterials. The mechanical matematerial fabricated by two-photon stereolithography can be embedded in a structural-color stimuli-responsive hydrogels to amplify the sensitivity (the change in structural color) (Figure 1). To prove this concept, we here constructed micro-scale mesh-like structures with negative poisson ratio. By responding to an applied displacement of 'z = 50 μm, this structure expanded to 'x = 90 μm, showing its displacement amplification. The fabricated structures embedded in poly-N-isopropylacrylamide (PNIPAM) hydrogel showed that the shrinkage of the PNIPAM hydrogel successfully drive the embedded mechanical-metamaterial structures. We believe that this system would be an effective approach to increase the sensitivity of the structural color gel sensors for practical applications.

Radiopaque hydrogel microfiber for arterial embolization

Takakura N., Ohta H., Komatsu T., Kurashina Y., Okano H.J., Onoe H.

ISSN 9781733419017

This paper proposes a radiopaque hydrogel microfiber for arterial embolization. The microfiber is made of barium alginate hydrogel containing zirconia (Radiopaque), and fabricated in a dual coaxial laminar flow microfluidic device. We confirmed that X-ray imaging was possible by encapsulating zirconia particles in hydrogel microfibers. Moreover the microfiber was successfully delivered into the target arteries of rats using a catheter to block blood flow for a long time. We believe that this microfiber would enable arterial embolization of cancerous tissues in various organs.

Quantitative design strategy of the resolution and screen area of microfluidic reflective display with sub-pixels

Muramatsu J., Onoe H.

ISSN 9781733419017

This paper discusses the design of the multi-color microfluidic display with sub-pixels. Our display has four primary color sub-pixels in the single pixel, and displays various colors by controlling the ON/OFF of sub-pixels. To show clear images, small sub-pixels and large screen are required, but the driving pressure of the fluid limits the design. Then, we calculated the driving pressure, and led the quantitative design strategy. Finally, we confirmed the smoother color mixing by high resolution and large screen display.

DNA Aptamer-Linked Structural-Color Hydrogel for Repeatable Biochemical Sensing

Hayashi T., Takinoue M., Onoe H.

2019 20th International Conference on Solid-State Sensors, Actuators and Microsystems and Eurosensors XXXIII, TRANSDUCERS 2019 and EUROSENSORS XXXIII （2019 20th International Conference on Solid-State Sensors, Actuators and Microsystems and Eurosensors XXXIII, TRANSDUCERS 2019 and EUROSENSORS XXXIII） 582 - 585 2019年06月

ISSN 9781728120072

© 2019 IEEE. This paper describes a DNA aptamer-linked structural-color hydrogel sensor that can quantitatively and repeatably detect biochemical substances through visual information without any specific equipment. The initial color of structural-color hydrogel could be adjusted by controlling the concentration of the colloidal silica particle. We co-polymerized a DNA aptamer that specifically binds to silver ions into acrylamide hydrogel and evaluated its quantitative shrinking response to silver acetate solution. In addition, we succeeded in initializing our DNA aptamer hydrogel sensor by heating, indicating that our chemical sensor could repeatably measure the target chemical substance for the long term. We believe that our structural-color biochemical sensor could be applied to various routine monitoring such as healthcare diagnosis and water safety.

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Stimuli-Responsive Structural Color Hydrogel Microbeads for Wearable Biometric Sensors

Tsuchiya M., Kurashina Y., Onoe H.

ISSN 9781728120072

© 2019 IEEE. This paper describes stimuli-responsive structural color hydrogel microbeads as sensing elements for wearable biometric sensors. Since the structural color with a curved surface has no angle dependency, spherical shape of microbeads is suitable for partial uses of structural color-based eye-recognizable sensors. As a first step for demonstrating our concept, we fabricated temperature responsive structural color hydrogel microbeads and confirmed those structural color clearly changed by the temperature change. These microbeads could be encapsulated in a wearable flexible device and the biological information could be properly measured from different viewing angles. We believe this wearable sensor with structural color microbeads could become an effective approach for sensing the environment and healthcare targets.

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Soft Spiral-Shaped Micro-Swimmer with Propulsion Force Control by Pitch Change

Yoshida K., Onoe H.

ISSN 9781728120072

© 2019 IEEE. This paper describes a soft spiral-shaped micro-swimmer with propulsion force controlled by pitch change. Soft spiral-shaped micro-swimmers, made of stimuli-responsive hydrogel encapsulating magnetic nanoparticles, were continuously formed by using a bevel-tip capillary. We achieved the pitch change of the double-layered micro-swimmer by temperature stimulus and confirmed that the propulsion force of the swimmer was controlled by the pitch change. We believe that our micro-swimmer could pave the way to various microscale biochemical applications such as autonomous soft-robots and soft micro-probes for intricate environment.

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Shape Deformation Analysis of Single Cell in 3d Tissue under Mechanical Stimuli

Kasahara K., Kurashina Y., Miura S., Miyata S., Onoe H.

ISSN 9781728120072

© 2019 IEEE. This paper describes an analytical platform to investigate the cell response against mechanical stimuli in in vitro 3D tissues. The system is capable of live-imaging cells in 3D tissues at a single cell level under mechanical stimuli, which makes this system similar to the in vivo environment and suitable for analysis of maturation mechanism. We succeeded in imaging various shapes of cells in 3D tissue under mechanical stimuli and observed that the stretch-induced deformation was distributed non-uniformly inside cells. We believe that our system could contribute to a further understanding of the tissue maturation mechanism induced by mechanical stimuli, which is highly useful for the development of tissue reconstruction.

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Multi-Hydrogel 4D Printing for Deformation Control

Uchida T., Onoe H.

ISSN 9781728120072

© 2019 IEEE. This paper describes a method to fabricate three-dimensional (3D) microstructures composed of multiple types of stimuli-responsive hydrogels. Using our method, multi-hydrogels 3D microstructures with internal gaps (ex. framed structure, beams structure etc.) can be printed and polymerized in supporting viscous liquid. We fabricated straight-line patterns composed of two types of hydrogels (pNIPAM: stimuli-responsive, and pAM: non-responsive). The printed multi-hydrogel structures were evaluated for the printing accuracy and the stimuli-responsivity to ensure their deformation controllability. Our proposed method would be an effective tool for creating multi-hydrogel 3D microstructures with various types of stimuli (optical, pH, molecular, etc.), for applications in soft actuators/robotics, and self-assembly/adaptive systems.

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Fabrication of metal microstructures in elastic hydrogel by multiphoton photoreduction

Terakawa M., Machida M., Onoe H., Niidome T., Heisterkamp A.

2019 Conference on Lasers and Electro-Optics Europe and European Quantum Electronics Conference, CLEO/Europe-EQEC 2019 （2019 Conference on Lasers and Electro-Optics Europe and European Quantum Electronics Conference, CLEO/Europe-EQEC 2019） 2019年06月

ISSN 9781728104690

© 2019 IEEE. Soft materials, including elastic polymers and hydrogels, are promising materials for soft robots, implantable devices, and wearable devices owing to their flexibility and biocompatibility. In recent years, the scope of use of such soft materials is expanding further because of their integration with metal micro- and nanostructures, which exhibit attractive optical and electrical properties. In this study, we demonstrate the formation of metal microstructures inside a hydrogel by photoreduction of metal ion by using femtosecond laser. Because the hydrogels have permeability to fluids, metal ions are able to be added by simply immersing the hydrogel into the metal ion solution. Femtosecond laser pulses were focused and scanned in the hydrogel to fabricate metal microstructures [1, 2]. The optical diffraction pattern obtained with the silver grating inside the hydrogel showed spaced diffraction spots, which indicated that a regular, periodic silver grating was formed. Notably, the distance between the diffraction spots changed when the water content in the hydrogel was reduced. The grating period decreased when the hydrogel shrank owing to the loss of water (Fig. 1(a)), but the straight shapes of the line structures were preserved, which demonstrated the optical tunability of the fabricated structure.

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ECM-based Stretchable Microfluidic System for in vitro 3D Tissue Culture

Shimizu A., Goh W.H., Hashimoto M., Miura S., Onoe H.

ISSN 9781728120072

© 2019 IEEE. We present an extracellular matrix (ECM)-based stretchable microfluidic system for in vitro three-dimensional (3D) tissue culture, which mimics the in vivo blood vessels. The target cells (ex. endothelial cells (ECs)) can be cultured with perfusion and stretch simultaneously in our proposed system. Our ECM (collagen)-based microfluidic device was fabricated by dissolving water-soluble sacrificial molds fabricated with 3D printer. We demonstrated perfusion and stretch of collagen microfluidic devices with culturing human umbilical vein endothelial cells (HUVECs), showing that the cultured cells were stretched along the expansion of the collagen microchannel. We believe that our collagen-based microfluidic stretch system could be a useful tool for understanding the mechanisms of vascular tissue formation and mechanotransduction.

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Graphene-Based Wireless Inline Pressure Sensor for in Vivo Blood Pressure Monitoring

Inoue N., Onoe H.

ISSN 9781728116105

© 2019 IEEE. This study describes a graphene-based wireless inline pressure sensor that can be easily inserted between an implanted microdevice and a blood vessel for in vivo blood pressure monitoring. Our wireless pressure sensor is simply composed of a graphene sheet (piezo-resistive sensor) attached on a microfluidic elastic tube and a coil wound up to the tube as a transmitter. The applied pressure inside the tube can be monitored wirelessly by an external receiver coil. We fabricated the sensor system applicable to monitoring the range of typical blood pressure, 10-18 kPa, by designing the sensitivity depending on the stiffness and the thickness of the elastic tube, the turn numbers of the coils, and the distance between the coils. Furthermore, we demonstrated to wirelessly measure the blood-pressure-mimicking pulsed inputs with our sensor that was embedded in a biological tissue. We believe that our wireless inline pressure sensor could be an effective tool for monitoring in vivo implanted medical devices such as microfluidic artificial kidneys.

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Thin Layered Heterogeneous Vascularized 3D Tissue Models Constructed with Separated-Layer Collagen Microtube

Itai S., Onoe H.

ISSN 9781728116105

© 2019 IEEE. We present an in vitro vascularized 3D cell co-culture, performed by a separated-layer collagen microtube device. Our device can co-culture endothelial and other cells in close position, while the collagen layers are separated into an outer support layer and an inner culture layer. The close distance between different types of cells enhances mutual cell interaction and enables us to observe the tissue structures clearly. Moreover, while collagen tubes are directly attached to silicone tubes, perfusion culture is easily performed by an external pump system. We believe that our device could help the fabrication of various vascularized tissue models in high activity, and contribute to the development of pharmacokinetic testing platforms and regenerative medicine.

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尾上 弘晃

論文 - 尾上 弘晃

尾上　弘晃

論文 - 尾上　弘晃