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This study reports a combinational method of tensile testing with TEM observation to observe the local area in a large magnified view. Our target material is single-crystal silicon that behaves in a brittle manner under tension until fracture in general. We developed a novel silicon chip for tensile testing of nanoscale silicon film with compliant mechanism for maintaining the observation point on the tensile specimen. The experimental results showed crack initiation and then incredibly crack shielding in single-crystal silicon under tensile loading.

This study reports our two unpredictable behaviors for fracture of nano-scale silicon with 100 nm thickness. We developed a novel tensile testing method conducted on silicon chip to observe a local area in large magnified view during tensile test. For comparing fracture behavior of 100 nm-thick silicon film with V-notch and U-notch, we performed FEM analysis to optimize the locations of notches. The results shows that V-notch generating large local stress-field at a notch root was stronger for tensile stress than U-notch.

This work proposes the detection method of chemotaxis which is behavioral response against chemical substance of C. elegans using capacitance sensor. We designed electrodes assembled with wave-shaped-microchannel. We fabricated chromium and gold membrane electrode on a glass plate. To detect behavioral response of C. elegans against chemical substance, we conducted experiment using chrome-gold membrane electrode for capacitance sensor.

Artificial cell sheet is utilized as a useful method for tissue engineering. We proposed a novel approach to fabricate the Ca-alginate gel sheet embedded liver cells to mimic the liver lobule tissue. Ca-alginate sheet with hepatic lobule shaped pattern was firstly deposited on a micro-electrode device based on the electrodeposition method. Viability of embedded cells was checked to be maintained more than 90%. What's more, we further stacked the fabricated cell sheets into a pre-designed PDMS mold. The stacked multi-layered 3D cell structure can contribute the possibility for the applications of artificial liver fabrication.

We studied bending of multilayered graphene into 3D structure. In this paper, we proposed a nanogripper folded by multilayered graphene as one of the 3D device. The nanogripper is actuated by electro static forces to open and close. The multilayered graphene was fabricated by focused ion beam (FIB) to form nano-gripper design. Reversible action is realized by controlled two different electrodes. In the experimental section, the relationship of actuation distance and applied voltage was evaluated for folded multilayered graphene.

Practical education about information security is needed for system developers and administrators in Web service suppliers. We propose a hacking contest CTF as attack and defense style with a website for a multiple online game. The contest organizer prepares a game server site as a contest environment which contains several vulnerability. The contest participants are divided into an attacker team as game players and a defender team as game Website operators. While the attackers access the game site with normal actions, they find vulnerabilities and try cheating actions. While the defenders monitor server logs, they detect illegal events and prevent them for maintenance. An action of each side is calculated as a point and makes each score for victory or defeat by the contest rule. The contest organizer reviews the progress situation with all participants. In this paper, we introduce several functions of a trial system and discuss the result of a trial practice.

Field-effect transistors (FETs) have been developed from silicon based to carbon nanotubes (CNTs) based, and the fabrication space became three-dimensionl (3D). Such fabrication process requires to accurately assemble a single CNT in 3D. However, most of the current assembly technologies were used for planar structures but not for 3D structures. In this study, we aim to use nanomanipulation based on a scanning electron microscopy (SEM) to realize the 3D assembly. To achieve this goal, we first proposed a novel 3D structure named Tri-gate CNT-FET. The Tri-gate CNT-FET has three cuboid micro-electrodes and it is wrapped by CNTs with front, top and back sides. After fabrication of the electrodes, a single CNT was picked up by an Au-coated probe and placed on the front side of the three micro-electrodes by suspending over a substrate to a certain height. The CNT pick-up and placement highly depended on attractive interactions at a CNT-metal contact interface by van der Waals force. Electron beam induced deposition (EBID) technique was then used to deposit Tungsten at the interface to fix CNT. Mechanical cutting was finally carried out to release the probe from the assembled structure. The whole assembly was achieved by using only one nanomanipulator. Experiment results validated our proposed 3D assembly method for the fabrication of Tri-gate CNT-FET.

Rotation manipulation of Caenorhabditis elegans (C. elegans) is presented for higher precision by a microchannel. The C. elegans was trapped within a biocompatible gel bead to rotate by a rotational motor. An alginate was used to form the gel bead. Without immobilization treatment by a sodium azide, the C. elegans moves during solidification of alginate. Then, a cavity was happened in the alginate gel bead. On the other hand, C. elegans was trapped without any cavity after immobilization treatment. The stopping and recovery motions of C. elegans were evaluated through the immobilization treatment experimentally. Finally, the eccentricity of rotational manipulation was evaluated with/without centering by a microchannel. The eccentricity was 35 % higher with the microchannel and high precision rotation was achieved at 0.03 degrees/step of actuator.

Helical structure assembled by hydrogel microfibers is significant for culture of smooth muscle cells. However, the helical structure is only fabricated at the macroscale, while the fabrication of helical microstructure is still a challenge due to the lack of assembly method. In this paper, we propose a robotics-based assembly method to handle such challenge. An electromagnetic needle (EMN) is employed as end-effector to magnetically reel the microfiber encapsulating magnetic nanoparticles around a micropillar, and a dual-ring structure is designed to keep the microfiber being attracted at the EMN tip. For enhancing the stability of tip attraction, the manipulation mode of anticlockwise pushing microfiber is established. Moreover, the interaction mechanism between EMN tip and microfiber is analyzed by developing a static force model, and then the key condition of stably reeling microfiber is concluded. Furthermore, a robotics-based motion trajectory of EMN tip is planned to achieve a smooth reeling process. Based on such planning, the size of dual-ring structure is further optimized to improve the success rate of reeling. Finally, the helical microstructure with there-turn coils is successfully fabricated.

This study presents the high-precision microinjection of fluorescent micro-gel beads into Caenorhabditis elegans trapped in a suction microchannel. In our previous works, we demonstrated survival microinjection by a conventional micromanipulation technique. However, the focal planes differed between the tip of the microinjection tool and the target axon inside the C. elegans body. To resolve this problem, we here propose a suction microchannel that traps C. elegans during the microinjection operation. The focal plane of the target nerve axon matches that of the fluorescent microbead in the microinjection tool, enabling high-precision microinjection into the interior of the C. elegans body under a microscopic view. In an experimental evaluation, the positioning accuracy of the injection into C. elegans was within the target accuracy (15 μm). The head-flrst navigation alignment of C. elegans along the microchannel was controlled by electrotaxis. Injection of the fluorescent micro-gel bead into the C. elegans body was quantitatively confirmed by confocal microscopy.

Medical simulator is important to improve the operation skills with training system for medical doctors. In this study, dura mater model of human brain is fabricated to aim in reproduction of 3D structure. To mimic the physical properties of actual dura mater tissue, we propose a dura mater model in which are embedded a fiber sheet in a silicone resin. A tensile test was carried out to evaluate the effect of fiber sheet inside silicone resin.

In this paper, we propose a new method to construct microchannels inside cell structures. A local melting of cell embedded hydrogel is employed to make microchannels inside cell structures. Local melting of hydrogel was conducted using the fabricated electrodes. Electrodes were fabricated using photolithography technique on a glass substrate. Electrode designs were prepared ladder-shape. The ladder-shape is used to demonstrate fabrication of arbitrary shapes of channel. The hydrogel block was placed on the electrodes and 100 μm width electrode was used to melt the hydrogel. The hydrogel was prepared at the concentration of 5.6 % gelatin and 1.4 % agar. The results indicate that the proposed method can be used to making vascular-like networks inside cell structures to construct in vitro 3D cell systems.

This paper reported a cell system that fabricates hepatic lobule-like microtissue (HLLM) based on alginate-Calcium electrodeposition and cell microcapsule method. The property of the fabricated HLLM includes: 1) With a shape similar to our native hepatic lobule tissue. 2) High cell dense (∼108). 3) Easily be moved and retrieved for further 3D assembly. Therefore, we proposed a repetitive single-step manipulation method to assemble these single HLLM into 3D multilayer hepatic lobule model. The pick-up success rate was approximating 90%. The assembly speed was about 0.4 microtissue/min and the cell viability was higher than 80%. Unlike other assembly methods, our method is sufficiently repeatable and easy to assemble many single micro modules. The fabricated 3D hepatic lobule model with high cell density is essential for tissue engineering applications.

Brain tumor is likely to be serious for human, and medical surgery simulator has been devised for training of their removal. In this study, we have focused on the soft brain tumor and propose the tumor model which is wrapped in thin membranes to the combination of water-absorbing polymers (main component: sodium polyacrylic acid salt) and viscous materials to be bonded by filling between them. This model has a reputation to be close to a kind of brain tumor.

In this study, the internal structure of collagen scaffold is observed by a scanning electron microscope-computed tomography (SEM-CT) technique operated inside an environmental-scanning electron microscope (E-SEM). The E-SEM is able to use maintain the aqueous condition inside the sample by controlling the temperature and pressure. We demonstrated the SEM-CT observation of collagen scaffold by culturing osteoblast cells in certain culture term, and confirmed the calcification change of osteoblast cells.

In this paper, a novel approach is presented to obtain the cell sheets with mimicking the morphology of liver lobule tissue by electrodeposition method. We would take some steps to gain the sheets. It includes: 1) fabricate microelectrode which coated pattern onto fluorine-doped tin oxide (FTO) glass based on photolithography technique. 2) electrodeposition experiment which embedded with RLC-18 (rat liver) cells. 3) detach the sheet from the microelectrode by shaking it. 4) assemble 3D tissue structure. In the result, precise pattern in the sheet could be kept and the viability of the cells could be maintained. We also checked the height of the sheet. We believe the use of cell sheets by electrodeposition method is great potential in fabricating 3D cell structures.

In this paper, we propose a new method to assemble microstructures with biological cells towards in vitro 3D cellular structures. The proposed assembly method uses self-assembly process of magnetized toroidal microstructures. Biocompatible toroidal hydrogel microstructures are prepared by electrodeposition method, and ferrite particles are put on the fabricated structures using poly-L-lysine (PLL). The microstructures are magnetized by the magnetic field at 3 T, and assembled by the magnetic self-assembly process. Biological cells were encapsulated in the microstructures and cultured to achieve high density of cells inside structures. The magnetized microstructures were assembled automatically. The magnetic force generated from the ferrite embedded microstructures was estimated and compared to the fluid resistance applied to the microstructures. The proposed method can be applied to achieve 3D in vitro cell structures with vascular networks for tissue engineering applications.

This paper presents a electrostatic actuation of multi-graphene which was folded by nanomanipulation for novel nano-gripper application. The development design of multi-graphene was initially fabricated by focused ion beam (FIB) process. The nanomanipulation system was used for folding and electrostatic actuation inside a FESEM (Field Emission Scanning Electron Microscope). The movement of multi-graphene was confirmed by electrostatic forces. The actuation was evaluated depending on the applied voltages.

Nanotool feeding system (NTFS) is presented for efficient nanomanipulation. We constructed a unique bio-nanomanipulation system inside an Environmental-SEM (E-SEM) using various nanotools, for example stiffness measurement nanotool, dual electrical nanoprobe, nanopicker, nanofork, nanocutter, nanoputter, and nanoinjector. For continues usage of different multiple tools, it needs to exchange the nanotools continuously. In this paper, the Rotary-table Nanotool Feeding System (R-NTFS) is proposed to realize continuous exchange of different multiple tools individually. An efficient continuous nanomanipulation was achieved by a short exchange time which was about 13 seconds. Finally, the multiple nanoinjection was demonstrated using the proposed R-NTFS.

In this paper, we conducted to assembly of microstructures for in vitro 3D cellular structures using self-assembly of magnetized hydrogels. The biocompatible hydrogel microstructures are fabricated by electrodeposition method and ferrite particles are coated on the structures with poly-L-lysine. The microstructures are magnetized by applying 3 T magnetic field, and assembled by the magnetic force. Biological cells can be encapsulated in the microstructures and cultured to achieve high density cell structures. The magnetic microstructures were assembled automatically to form tube structures. The magnetic force generated from the ferrite embedded microstructures was estimated and compared to the fluid resistance applied to the microstructures. The assembly of microstructures was achieved using a shaker to shake the structures inside liquid. The proposed method can be applied to assemble 3D cell structures with vascular-like channels for tissue engineering applications.

This paper presents a novel In situ nanomanipulation integrated with scanning electron microscope- computed tomography (SEM-CT) imaging system for 3D nanomanipulation.

Semiconductor nano-devices based on carbon nanotubes (CNTs) have attracted great interests recently such as field effect transistors (CNTFETs). One of the challenges is to reduce the contact resistance between CNT and electrodes. This paper presents a robotic system with two nano-manipulators for two-lead contact resistance measurement. Electron beam induced deposition (EBID) technique was applied to decrease the contact resistance between multi-walled CNTs (MWCNTs) and Tungsten deposition fabricated by focused ion beam (FIB). A Tungsten (W) probe fixed on one manipulator is used to pick up a CNT selectively from a CNT bundle. The picked CNT was positioned to approach a W deposition on an atomic force microscopy (AFM) cantilever. The cantilever mounted on another manipulator was coordinated by positioning for well contact between the W deposition and CNT. To strengthen this contact, four W points are deposited on the contact area of CNT for totally 9min by EBID. A resistance between W probe and cantilever was measured before and after EBID. Based on these measured resistance, contact resistance was calculated by a theoretical model. It showed the contact resistance of MWCNT/Tungsten deposition was reduced by 98.8% by the EBID deposition.

This paper presents a local guiding of Caenorhabditis elegans (C. elegans) inside a micro-channel. We are interested in the nerve analysis using C. elegance as a model organism. As previous work, a micromanipulation system was used for local drug micro-injection under an optical microscope (OM) into C. elegans, however it was difficult to control the position or posture of individual C. elegans on a normal dish. In this work, micro-injection system was proposed to conduct the microinjection for individual C. elegans. electrotaxis of C. elegans was used to guide in a micro-channel. The electrotaxis is one of the natural feature of C. elegans by changing their movements depending on the electric field. It was confirmed that C. elegans moved from anode to cathode in a microfluidic channel when an electric field was applied. Two micro-channels were designed to compare the effectiveness of guiding the C. elegans to the injection point which is almost same width with C. elegans. The proposed device will be used for high accurate or efficient micro-injection to C. elegans.

In this paper, we constructed three dimensional (3D) microchannel networks inside gelatin-based hydrogel towards 3D in vitro cell structures. To achieve functional 3D cell structures, vascular networks are important to supply oxygen and nutrients to cells, and remove waste product from cells. An alginate hydrogel fibers were employed to construct the microchannel networks like blood vessels. The pattern of the hydrogel fiber can be fixed using magnetic force and the fibers are embedded in the gelatin-based hydrogel. Cells can be embedded inside the gelatin-based hydrogel. The patterned hydrogel fiber can be melted using standard saline citrate (SSC) buffer and the melted area can be used as vascular networks. The flow inside the melted alginate hydrogel fibers were visualized using fluorescent microbeads. The results validate that the proposed method can be used to make arbitrary patterns of vascular networks inside cell structures and contribute to achieve in vitro 3D cell structures.

Micro flexible electrodes were fabricated to stimulate peripheral nerve for a rodent model. This paper proposes two types of micro electrodes to stimulate peripheral nerve of lab mouse which has an interval in 600 µm. One is a type of electrode which is able to be fully embedded into the lab mouse body, and the other is partially embedded type. A thin polyimide film was used for high flexibility and biocompatibility, so that it could deformed along to nerve shape with surface tention. By suturing to the peripheral nerve of lab mouse, its foot was stimulated using the fabricated micro flexible electrode. We confirmed a leg of the lab mouse took an involuntary motion by receiving an electrical stimulation on sciatic nerve from the fabricated micro flexible electrode.

In this paper, we propose a method of cell assembly on microstructures of a biodegradable material for the regeneration of living tissue. The adhesion of fabricated biodegradable structures on the substrate was one of the important challenges. The material was tested trypsin EDTA-dipped Dialysis membrane. The results show that one side of the microstructure after 2 minutes was peeled off, but I did not peel off the other side.

In situ nanomanipulation system is presented with 3D scanning electron microscope - computed tomography (SEM-CT) system integrated with inside an environmental - SEM (E-SEM). The E-SEM was used to achieve a real-time high resolution imaging for high precision nanomanipulation. The SEM-CT system was used for obtaining 3D cross-sectional image with sub-micron high resolution. In this paper, Caenorhabditis elegans (C. elegans) was used as a target of biological sample to demonstrate a nanoinjection operation. The nanoinjection was determined by the SEM-CT system with its 3D information.

In this paper, we propose a new method to construct microchannels inside cell structures. A local melting of cell embedded hydrogel is employed to make microchannels inside cell structures. The fabricated microchannels can be used as vascular-like networks to supply nutrition and oxygen to cells. Electrodes were fabricated using photolithography technique on a glass substrate. The hydrogel to embed cells were prepared by mixing gelatin and agar in culture media. A microchannel was experimentally fabricated using the fabricated electrodes to locally melt the hydrogel on the electrodes. The fabricated channel width and height by local heating was changed proportionally by the heating time when the applied voltage to the electrodes was constant. The results indicate that the proposed method can be used to making vascular-like networks inside cell structures to construct in vitro 3D cell systems.

In this study, we describe a novel method of fabricating shape-controlled calcium alginate gel microcapsules. Alginate-poly-L-lysine (PLL) hydrogel microcapsules with predefined shapes were constructed based on electrodeposition method. Firstly, electrolysis of water in alginate solutions with calcium carbonate particles induced alginate gelation on micro-patterned electrode to form 2D gel structures. Then, these structures will be detached from the electrode surface and treated with the alginate-PLL microcapsules system. By passive control based on the micro-pattern geometric confinement and electrodeposition parameters, we succeeded in producing calcium alginate-PLL microcapsules with diverse shapes (such as sphere rod and cubic). The shape and size of the calcium alginate microcapsules could be tuned by adjusting the geometric design of micro-pattern on electrode and the apply voltage of electrodepostion. The preparation conditions of size- and shape-controlled calcium alginate-PLL microcapsules and influence factors were studied. This proposed method can lead to more accurate and creative studies of fabricating biocompatibility scaffold for tissue engineering.

This paper proposes an electrodeposition-based method to generate Alginate-Poly-L-lysine (PLL) microcapsules for 3D cell structures. Hepatic lobule shaped microcapsules of RLC-18 cells were produced for long-term culture to obtain desired morphologies of cell aggregates. The fabricated hepatic lobule models with high cell density are important to be applied for 3D assembly of biological cells for tissue engineering applications.

This paper presents a fabrication method of multi-graphene box structure by a nanomanipulation in a Field Emission Scanning Electron Microscope (FESEM). To bend the multi-graphene in plastic deformation region, the bending stress were measured using a silicon cantilever based on the nanomanipulation. In this study, defects were introduced inside the multi-graphene on the folding line of the multi-graphene by irradiating an electron beam assisted with oxygen gas. From experimental bending stress measurement, the bending stress was dropped with electron beam irradiation in oxygen gas environment. The fabrication of 3D box structure of multi-graphene was demonstrated from a cubic net of multi-graphene which was fabricated by a Focused Ion Beam (FIB) etching process. For bending the one side of the cubic net graphene, a tungsten probe was used after reforming by FIB etching as end-effector of nanomanipulator. The multi graphene was bent to form a box structure in 3D space.

A nanolaboratory is one of the systems to realize various nanoscale fabrications and assemblies to develop novel nanodevices to integrate borderless technologies based on a nanorobotic manipulation system. We have presented the nanolaboratory inside electron microscopes including a transmission electron microscope (TEM), scanning electron microscope (SEM), and environmental-SEM (E-SEM) for three-dimensional (3D) and real-time nanomanipulation, nanoinstrumentation, and nanoassembly. The following is a presentation of our current work of nanomanipulation and nanoassembly based on the hybrid nanorobotic manipulation inside a TEM and an SEM toward carbon nanotube (CNT) applications. Single cell stiffness measurement has been also presented based on the nanorobotic manipulation system inside an E-SEM.

In this study, cell-laden alginate-poly-L-lysine (PLL) hydrogel structures with arbitrary shapes were constructed based on electrodeposition method. Electrolysis of water in alginate solutions with calcium carbonate particles induced alginate gelation on micro-patterned anode electrode, and cell-laden alginate gel structures were formed. The several different shapes of gel were generated at one time by predefined micro-patterns. The micro-patterned electrode was fabricated by coating photoresist on Fluorine-doped tin oxide (FTO) glass slide. Alginate-PLL encapsulation technique was introduced to this platform forming alginate-PLL hydrogel structures. This proposed method can lead to more accurate and creative studies of fabricating cell-laden scaffold for tissue engineering.

This study presents the survival microinjection into Caenorhabditis elegans (C. elegans) with in vivo observation based on micromanipulation. The microinjections were achieved with micro-gel beads which are enable to encapsulate chemicals for injection. In this study, a fluorescent material was used to evaluate the injection positional precision inside the C. elegans. The fluorescent microbead was picked up at the tip of a micropipette injection tool and injected by a piezo actuated microinjector. The distance between the injected micro-gel bead and closest nerve axon was measured as 20.3 µm and 16.5 µm by in vivo observation of a confocal microscopy. The two types of pipette tools were used to evaluate the success and survival rates of microinjection, and the smaller pipette (pipette A, 0.8 µm in diameter) showed higher rates as 50 % and 67 % respectively.

The fabrication of vessel-mimetic microchannel provides critical access to enable sufficient nutrient delivery for engineered composite tissues. This paper presents a novel method to engineer vascular-like microchannel by automated assembly of donut-shaped micromodules embedding fibroblast cells. A railed microrobotic system is set up with multi manipulators of 30 nm positioning resolution under an optical microscope. The coordinated manipulation among the micromanipulators is performed with newly designed concentric movement along the rail, which realized the arbitrary change of micromanipulator posture. With the novel developed image processing algorithm for the tracking of micromanipulator and micromodules, the automated bio-assembly of vascular-like microchannel is achieved which is free from the influence of the occlusion during contact manipulation. Experimental results showed that the pick-up success rate is around 98% and tracking algorithm is robust. Finally, we achieved automated assembly of microchannel at a speed of 6 micromodules/min, which is efficient enough to fabricate vessel-mimetic substitute with macro-significance dimension for biological application.

In this paper, we constructed three dimensional (3D) microchannel networks inside gelatin-based hydrogel towards 3D in vitro cell structures. The 3D in vitro assembly of cells is one of the important techniques to reveal cell growth, differentiation and hystogenesis for applications in tissue engineering, drug screening, and cell characterization. To achieve functional 3D cell structures, vascular networks are necessary to supply oxygen and nutrients to cells, and remove waste product from cells. Alginate hydrogel fibers were employed to construct the microchannel networks like blood vessels in this paper. The patterned hydrogel fibers are embedded in the gelatin-based hydrogel as a mold of microchannels. Cells can be embedded inside the gelatin-based hydrogel. The patterned hydrogel fiber can be melted using standard saline citrate (SSC) buffer and the melted area can be used as vascular networks. The gelatin and agar are mixed to make gelatin-based hydrogel which cannot be melted at 37 °C. The flow inside the melted alginate hydrogel fibers were visualized using fluorescent microbeads and nanobeads. The results validate that the proposed method can be used to make arbitrary patterns of vascular networks inside cell structures and contribute to achieve in vitro 3D cell structures.

This paper presents (he aqueous observation of three-dimensional internal information using scanning election microscope- computed tomography (SEM-CT) inside an environ mental-SEM (E-SEM). For this purpose, it Is required to control the sample temperature by controlling sampk' duimhiT pressure of the E-SEM. In this paper, a cooling system was installed into the SEM-CT system to decrease the sample temperature. 1 he aqueous observation was confirmed by the E-SEM and SEM-CT observations using sodium poh/acrylate particles as a sample.

Muhi-graphene cubic structure was fabricated by a nanomanipulation system. Two nanomanipulators were coordinately used with three degrees of freedoms to handle two end-effectors respectively. A cubic net was designed and fabricated using a multi graphene by a FIB (Focused Ion Beam) etching. A tungsten probe was also reformed by the FIB etching to adjust the size of cubic net design for bending manipulation. 1 he each surface of cubic net was bent to form a cubic 3D structure. In this study, the bending stress of multi graphene were also measured using a silicon cantilever to reveal the elastic or plastic deformation regions by bending manipulation.

Although a variety of carbon nanotube field-effect transistors (CNTFETs) have been successfully fabricated, the contact property between multi-walled carbon nanotubes (MWCNTs) and electrodes is still elusive. In this study, we aims at further characterizing the contact properties among MWCNTs, Au electrode (gold coated glass substrate) and tungsten deposit. First, an atomic force microscope (AFM) cantilever actuated by a nanorobotic manipulation system was used to move the MWCNTs to directly contact Au electrode or tungsten deposit. With the adjustment of contact length, the contact resistance could be derived by a theoretical model using two-lead method. We measured the resistance between the AFM cantilever and Au electrode or tungsten deposit before and after fixing MWCNTs with electron beam induced deposition (EBID).The results imply that the contact resistance decreased ∼11%after being fixed with EBID. Moreover, EBID is confirmed to be able to strengthen the contact between MWCNT and tungsten deposit.

Cell culture is a basic and significant task in biological engineering. Many cell culture works have been studied up to now. However, the cell is always cultured in a 2D plate in current techniques. Thus, the cells can only growth on a flat plate, which condition is far from that in vivo. Hydrogel is a kind of biocompatible material, inside with the cell can spread and growth. It provides us a method to study the cell's property in real 3D environment. Thus, how to control the shape of the gel is an important topic. In this paper, we proposed a method to control the gel's shape and position based on the manipulation of the anode electrode. The gel generation is based on the electrodeposition of calcium alginate. The reaction speed is controlled by the applied current. Three examples were demonstrated to show how our system is working. The result shows that straight gel line, arbitrary gel shape on substrate and multi-layer gel structure can be obtained by this proposed method.

In this paper, we conducted a new method to assemble microstructures inside a droplet named “Lab in a Droplet (LiD)”. The method can realize the assembly of micro-nano structures inside a droplet size. The surface tension is used to assemble microstructures automatically. Micro-scale or nano-scale objects are ejected from an inkjet nozzle. They are gathered at the center of the droplet and assembled by the surface tension. We conducted preliminary experiments to check whether the self-assembly of microstructures can be achieved by LiD. The experimental results show that the self-assembly of microbeads is conducted inside a droplet. The nano-scale objects can be patterned on a substrate depend on their sizes. A microstructure made of photo-crosslinkable resin was prepared, and microbeads were assembled with the microstructure inside a droplet. The method can be used for autonomous assembly of micro-nano structures in high precision.

Due to the poor controllability in hydrogels, Hydrogels-based assembly to form larger 3D complex shapes is still a big challenge. In this paper, we have reported a novel “bottom-up” method to fabricate three-dimensional (3D) magnetic alginate microfibers (MAMs) assemblies with complex shapes. Specifically, Alginate microfibers encapsulating Fe 3 O 4 magnetic nanoparticles (MNs) and fibroblasts (NIH/3T3) have been spun using microfluidic method with “pinch-off” scheme. Experimental results show that the MAMs can respond quickly to the magnetic field, enabling their enhanced controllability. The magnetic assembly system is constructed by PDMS microfluidic device, 3D supporting model adhered on the bottom surface of dish filled with deionized water and magnet. The microfluidic “printing“ and magnetic deposition in magnetic assembly process are experimentally demonstrated, respectively. Because of magnetic field, the complex assembly shapes can be fabricated just by moving the microfluidic device in a plane. To match well with the shape of supporting model and to keep a stable assembly structure, the secondary cross-linking method is employed. From the LIVE/DEAD assay, cells can survive well during the magnetic assembly process.

This paper presents a local microinjection system using hydro-gel beads based on micromanipulation near nerve axon of Caenorhabditis elegans (C. elegans), which is one of the important model organism for disease analysis and nerve analysis. The hydro-gel beads were prepared using Polyethylene Glycol Diacrylate (PEG-DA) to encapsulate biomaterials. The tip of micro-pipette tool was used to attach the hydro-gel beads by a negative pressure with a syringe. The local-nano-injection technique was demonstrated to inject fluorescent materials into C. elegans using the micro-pipette tool by a piezo actuator. The microinjection was evaluated in a three dimensional space by a confocal microscope. The proposed microinjection method is considered to be important as future micro-nano surgery system for life innovation using model organism.

In this paper, we presented a lab-on-chip microfluidic system for single cell mass measurement. Single cell mass has been related with drag force exerted on cell and Newton law of motion. Drag force has been generated using pressure driven syringe micropump. Motions of the cells were measured using optical observation under an inverted microscope. We have calibrated the approach using known mass of polystyrene microbeads with a diameter of 5.2 µm. Our experimental results showed that, mass of single microbead is 88.9 fg, which is very close to the theoretical mass (77.3 fg) of the particle. From which it is believed, our approach is suitable for single particle's mass measurement. We used Saccharomyces cerevisiae baker's yeast cell as a cell sample. Yeast cells have been cultured in our laboratory using YPD medium. For the diameter of 4 µm cell, mass of single cell was measured as 1.9 pg which is very consistent with previously reported single yeast cell mass (1–3 pg).

In this paper, we propose a method of cell assembly on microstructures of a biodegradable material for the regeneration of living tissue. The adhesion of fabricated biodegradable structures on the substrate was one of the important challenges. 5 different surface conditions were tested to prevent the adhesion: glass, 1.5 % agar, 1.5 % dried agar, mineral oil and glass treated by waterproof coating. The results show that the movable structure made of GelMA was not achieved in the conditions and require other materials to realize movable structures.

In this paper, manipulation of cell spheroids was conducted to construct 3D cell structures for tissue engineering applications. The spheroids were manipulated using thermoresposnive gel, and the cell viability was checked. The manipulated cells show more than 90 % viability. The results indicate that the spheroids can be assembled inside thermoresponsive polymer solution to construct 3D in vitro cell systems with keeping their live conditions.

Computer topography (CT) imaging is one of the powerful-tools for nondestructive observation technique. In this paper, we present observation of bone from mice by scanning electron microscope (SEM)-CT system using environmental- SEM (E-SEM). The advantage of this SEM-CT system is able to image in high-resolution with less than 400 nm resolution. We investigated the effects of X-ray wavelengths and intensities to improve the imaging contrast for SEM-CT observation. From experimental results, a porous structures were observed inside the bone sample with approximately 10 μm pores.

We present the fabrication of catalytic driven micro-nano robot by direct laser writing. The micro-nanorobot has a spiral design of 3,5, and 7 μm named D1, D2 and D3 respectively and a flat top design D4. The micro-nanorobot is catalytically driven in 6% hydrogen peroxide (H 2 O 2 ) from platinum catalytic area. The result shows that the spiral micro-nanorobot increased in speed except when the micro-nanorobot exhibits the drilling motion. It showed spinning motion, self-propulsion and drilling motion for micro-nanorobot D1, D2 and D3 respectively. The flat top micro-nanorobot has the highest speed and spinning motion was displayed. Future studies should include the actual pollutants in the environment and the effects of the drilling motion on its final content should be observed.

In this paper, an electrodeposition method was applied to construct cell patterning structures by an alginate hydrogel. The liver cells (RLC-18) were trapped selectively within alginate structures on the micro-patterning electrodes, which were fabricated by a photo-lithography process in circular, ring, and triangle structures. The living conditions of RLC-18 cells were confirmed until 3 days. These results indicate that biological cells were entrapped inside arbitrary shape hydrogel structures in living conditions. The fabricated 2D biological structures are important to be applied for 3D assembly of biological cells for tissue engineering applications.