Akihiko Ichikawa

Meijo University, Nagoya, Aichi, Japan

Are you Akihiko Ichikawa?

Claim your profile

Publications (39)26.72 Total impact

  • A. Ichikawa · S. Sakuma · F. Arai · S. Akagi
    [Show abstract] [Hide abstract]
    ABSTRACT: We have developed a highly functional untethered micro-robot that can manipulate cells with high gripping force in a micro-fluidic chip. The robot has gripping mechanism for grasping and transportation of cells with sufficient power. A permanent magnet is attached at the center of the gripping mechanism, and an electrical magnet controls the position of the magnet from the bottom of the micro-fluidic chip. The distance accuracy of the gripper is 3.0 μm, and it can activate about 50 Hz. The robot has four permanent magnets for positioning, and other four permanent magnets control the robot from the bottom of the micro-fluidic chip. The robot is made very thin and small to allow maneuverability in a micro-fluidic chip. We succeeded in high-power handling and cutting of a cell using this micro-robot.
    No preview · Article · Sep 2014 · Proceedings - IEEE International Conference on Robotics and Automation
  • [Show abstract] [Hide abstract]
    ABSTRACT: We propose a novel on-chip enucleation of an oocyte with zona pellucida by using a combination of untethered microrobots. To achieve enucleation within the closed space of a microfluidic chip, two microrobots, a microknife and a microgripper were integrated into the microfluidic chip. These microrobots were actuated by an external magnetic force produced by permanent magnets placed on the robotic stage. The tip of the microknife was designed by considering the biological geometric feature of an oocyte, i.e. the oocyte has a polar body in maturation stage II. Moreover, the microknife was fabricated by using grayscale lithography, which allows fabrication of three-dimensional microstructures. The microgripper has a gripping function that is independent of the driving mechanism. On-chip enucleation was demonstrated, and the enucleated oocytes are spherical, indicating that the cell membrane of the oocytes remained intact. To confirm successful enucleation using this method, we investigated the viability of oocytes after enucleation. The results show that the production rate, i.e. the ratio between the number of oocytes that reach the blastocyst stage and the number of bovine oocytes after nucleus transfer, is 100%. The technique will contribute to complex cell manipulation such as cell surgery in lab-on-a-chip devices.
    No preview · Article · Jul 2014 · Journal of Micromechanics and Microengineering
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Influenza virus attaches to sialic acid residues on the surface of host cells via the hemagglutinin (HA), a glycoprotein expressed on the viral envelope, and enters into the cytoplasm by receptor-mediated endocytosis. The viral genome is released and transported in to the nucleus, where transcription and replication take place. However, cellular factors affecting the influenza virus infection such as the cell cycle remain uncharacterized. To resolve the influence of cell cycle on influenza virus infection, we performed a single-virus infection analysis using optical tweezers. Using this newly developed single-virus infection system, the fluorescence-labeled influenza virus was trapped on a microchip using a laser (1064 nm) at 0.6 W, transported, and released onto individual H292 human lung epithelial cells. Interestingly, the influenza virus attached selectively to cells in the G1-phase. To clarify the molecular differences between cells in G1- and S/G2/M-phase, we performed several physical and chemical assays. Results indicated that: 1) the membranes of cells in G1-phase contained greater amounts of sialic acids (glycoproteins) than the membranes of cells in S/G2/M-phase; 2) the membrane stiffness of cells in S/G2/M-phase is more rigid than those in G1-phase by measurement using optical tweezers; and 3) S/G2/M-phase cells contained higher content of Gb3, Gb4 and GlcCer than G1-phase cells by an assay for lipid composition. A novel single-virus infection system was developed to characterize the difference in influenza virus susceptibility between G1- and S/G2/M-phase cells. Differences in virus binding specificity were associated with alterations in the lipid composition, sialic acid content, and membrane stiffness. This single-virus infection system will be useful for studying the infection mechanisms of other viruses.
    Full-text · Article · Jul 2013 · PLoS ONE
  • Source
    Lin Feng · Masaya Hagiwara · Akihiko Ichikawa · Fumihito Arai
    [Show abstract] [Hide abstract]
    ABSTRACT: In this study, we developed a microfluidic chip with a magnetically driven microrobot for oocyte enucleation. A microfluidic system was specially designed for enucleation, and the microrobot actively controls the local flow-speed distribution in the microfluidic chip. The microrobot can adjust fluid resistances in a channel and can open or close the channel to control the flow distribution. Analytical modeling was conducted to control the fluid speed distribution using the microrobot, and the model was experimentally validated. The novelties of the developed microfluidic system are as follows: (1) the cutting speed improved significantly owing to the local fluid flow control; (2) the cutting volume of the oocyte can be adjusted so that the oocyte undergoes less damage; and (3) the nucleus can be removed properly using the combination of a microrobot and hydrodynamic forces. Using this device, we achieved a minimally invasive enucleation process. The average enucleation time was 2.5 s and the average removal volume ratio was 20%. The proposed new system has the advantages of better operation speed, greater cutting precision, and potential for repeatable enucleation.
    Full-text · Article · Jun 2013 · Micromachines
  • A. Ichikawa · S. Sakuma · T. Shoda · F. Arai · Satoshi Akagi
    [Show abstract] [Hide abstract]
    ABSTRACT: We developed a highly functional untethered micro-robot that can manipulate cells with high gripping force in a micro-fluidic chip. The robot has gripping mechanism which is actuated by magnetic power. A permanent magnet is attached at the center of the gripping mechanism, and an electrical magnet controls the position of the magnet from the bottom of the micro-fluidic chip. The open-close accuracy of the gripper is about 3.0 μm. We succeeded in cutting of zona pelucida of oocyte and enucleation by using this micro-robot.
    No preview · Conference Paper · Jan 2013
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In this study, we present a smooth enucleation process on a microfluidic chip. To improve the success rate of enucleation and increasing the potential viability of the enucleated oocyte, a microfluidic system is specially designed. Magnetically driven MicroTool (MMT) control the flow distribution in the microchamber. Designed microchannel with height difference is for the purpose of confining oocyte with its nucleus located in the withdrawal microchannel to achieve the high precision control in cutting volume. By utilizing these aspects, first, oocytes are sequentially loaded to the operation port; MMT constrains the oocyte location and controls the distribution of micro flow simultaneously letting hydraulic force cut off the nucleus from the oocyte. Enucleated oocyte is smooth in shape and incision is neat. With cutting volume control, this system can achieve high-speed enucleation with less cutting volume while removing the nucleus. Since the flow distribution could be managed by MMT significantly, therefore, the new system is proposed here to show advantages by the means of operation speed, cutting precision and great potentiality on continuous cutting process.
    Full-text · Conference Paper · Oct 2012
  • Masaya Hagiwara · Akihiko Ichikawa · Tomohiro Kawahara · Fumihito Arai
    [Show abstract] [Hide abstract]
    ABSTRACT: We have developed novel microfluidic chip for enucleation of oocytes by magnetically actuated microrobots. Si and Ni composite microrobot driven by permanent magnets was developed and used as high power, high speed and high accuracy microarm to transport, rotate and cut swine oocyte in a microfluidic chip. The novelties of developed microrobot are as follows. 1) The drive frequency capability of microrobot improved by 10 times comparing to previously developed microrobot. 2) Si-Ni composite microrobot has no risk of biocompatibility. 3) A force of order of millinewton can be outputted from permanent magnets. The microfluidic chip was specially designed by fluid analysis of FEM for stable supply of the oocytes to the MMT manipulation area from the inlet. The integration of this high speed microrobot and microfluidic chip enables high throughput enucleation process in a microfluidic chip.
    No preview · Article · Mar 2012
  • L. Feng · M. Hagiwara · A. Ichikawa · F. Arai
    [Show abstract] [Hide abstract]
    ABSTRACT: We present a continuous enucleation process of bovine oocytes on a microfluidic chip to achieve the continuous cutting of the oocytes and increasing the potential viability of the enucleated oocyte. By combining microfluidic chip and micororobotics. the flow in a channel can be actively controlled and we achieved successive operations of 1) loading oocyte, 2) control cutting volume and 3) removing nucleus. The magnetically actuated microrobot can control local fluid flow by changing its position like gate valve and control fluid force distributions in a microchip which govern oocyte movement in a chip. The optimally designed microchannel for enucleation enables continuous operation and cutting bovine oocyte with smooth manner by hydrodynamic force.
    No preview · Article · Jan 2012
  • Source
    Lin Feng · A. Ichikawa · F. Arai · M. Hagiwara
    [Show abstract] [Hide abstract]
    ABSTRACT: We present a continuous enucleation process of bovine oocytes on a microfluidic chip to achieve the continuous cutting of the oocytes and increasing the potential viability of the enucleated oocyte. By combining microfluidic chip and micororobotics, the flow in a channel can be actively controlled and we achieved successive operations of 1) loading oocyte, 2) control cutting volume and 3) removing nucleus. The magnetically actuated microrobot can control local fluid flow by changing its position like gate valve and control fluid force distributions in a microchip which govern oocyte movement in a chip. The optimally designed microchannel for enucleation enables continuous operation and cutting bovine oocyte with smooth manner by hydrodynamic force. The new system is propose here to show advantages by the means of the continuous operation on oocytes in a short term, cutting precision and great potentiality on continuous enucleation process for clone technology.
    Full-text · Conference Paper · Jan 2012
  • A. Ichikawa · F. Arai
    [Show abstract] [Hide abstract]
    ABSTRACT: We have developed a novel on-chip micro-tool that can act as a pipette. This micro-pipette comprised a pump and nozzle. The pump had a membrane made of a negative photoresist sheet. The membrane was pumped by permanent magnets, and a cell was aspirated and fixed at the tip of the nozzle. The thickness of the membrane was designed with the help of FEM analysis results. We established the fabrication process of the micro-pipette to create a hollow structure using a negative photoresist sheet. The pumping quantity of the micro-pipette was measured while varying the power of the magnets, and the pumping quantity can be controlled by adjusting the distance between the magnets. The maximum pumping quantity was 34.1 nl. Based on the measurement results, we estimated the aspiration force to be 3.41 μN. In order to confirm the calculation results, the aspiration force was measured using a cantilever made from a negative photoresist and determined to be 7.6 μN. Finally, we performed single-cell manipulation using the micro-pipette.
    No preview · Article · Jan 2012 · Proceedings of the IEEE International Conference on Micro Electro Mechanical Systems (MEMS)
  • A. Ichikawa · S. Sakuma · F. Arai
    [Show abstract] [Hide abstract]
    ABSTRACT: We have developed an on-chip untetherd robot, which has suction mechanism. The robot has a pump activated by a permanent magnet and an electrical magnet. The robot is manipulated and positioned by permanent magnets. We established the fabrication process of the nano-pipette on the robot by using negative-photoresist sheet to make hollow structure. We performed the experiment of manipulation of bovine oocyte with the robot, and loading of a bovine oocyte from cell chamber to micro-channel.
    No preview · Conference Paper · Jan 2012
  • L. Feng · M. Hagiwara · A. Ichikawa · Y.L. Sun · F. Arai
    [Show abstract] [Hide abstract]
    ABSTRACT: We present an enucleation process with ejection module of bovine oocytes on a microfluidic chip to achieve the high speed enucleation of the oocytes and ejection of enucleated oocyte to the culture environment. By combining microfluidic chip and micororobotics, the flow in a channel can be actively controlled and we achieved successive operations of 1) loading oocyte, 2) control cutting volume and 3) removing nucleus, 4) dispensing enucleated oocyte immediately. After enucleation process, enucleated oocyte could be ejected to the culture well immediately, and ejected oocytes are neatly arranged in the culture array, this shows great ease of single oocyte operation. The magnetically actuated microrobot can control local fluid flow by changing its position like gate valve and control fluid force distributions in a microchip which govern oocyte movement in a chip. The optimally designed microchannel for enucleation enables continuous operation and cutting bovine oocyte with smooth manner by hydrodynamic force. Removed nucleus is thrown away from withdrawal microchannel, however the remaining part of oocyte dispensed from the nozzle hole is collected by a culture array.
    No preview · Conference Paper · Jan 2012
  • A. Ichikawa · F. Arai
    [Show abstract] [Hide abstract]
    ABSTRACT: We have developed a high-functional untetherd micro-robot which can manipulate cells with high-power suction. The robot is made thinly and small to maneuver in a micro-fluidic chip. A nozzle is fabricated by photolithography using SU-8. The robot has a suction pump activated by an electrical magnet and permanent magnet. We realized high-power suction of micro-scale robot by a miniaturization of cross-section of the nozzle and a speed-up of the pumping using electrical magnet and elastic PDMS membrane. We succeeded in high-power fixation and high-speed transportation of cells using this micro-robot. We also succeeded in cell loading with this robot and micro-fluidic chip.
    No preview · Conference Paper · Jan 2012
  • Akihiko Ichikawa · Fumihito Arai
    [Show abstract] [Hide abstract]
    ABSTRACT: We have developed an on-chip micro-robot, which has ability of pipetting such as cell injection, local regent blow, enucleation, air bubble generator, piercing cells, and micro-manipulation, made by SU-8 photoresist for cloning, chimera technology, cell assays, and artificial lipid bilayer membrane making. We used the property of SU-8 which has a sufficient stiffness enough to penetrate cells as well as a sufficient softness enough to provide pumping functions, which is unlike a glass or silicon materials. Using this material, we improved our magnetically-driven micro-tool (MMT) as a multifunctional micro-tool.
    No preview · Article · Nov 2011
  • [Show abstract] [Hide abstract]
    ABSTRACT: In the field of bioscience, such as regeneration medicine and cloning, the manipulation and analysis for cells are performed by many researchers. However, manual oper- ation for such micro objects is not feasible and practical for beginner operators. As for the problem, we have developed a two-fingered microhand supporting manual operation. Using the microhand, we can manipulate cells i.e., grab, rotate, carry, and so on - like when using chop sticks. The stiffness measurement of a cell is a key approach in single cell analysis techniques. It is important in indicating cell condition, because the stiffness of a cancer cell is lower than that of a normal cell as an example. However, measuring stiffness is very difficult, because deformations of cell are plasticly, and many researches to measure the stiffness of cell don't deal with plastic deformation. So, in this paper, the cell hardness is calculated instead of cell stiffness by measuring the reaction force caused in the process of cell deformation via a micro force sensor attached to the end-effector of the microhand. Our results point out that this can be one efficient measurement method for acquiring cell hardness. In this paper, three topics are discussed. First one is the fabrication of the end-effector with micro force sensor. Second one is the method of measuring hardness of cell. As a last one, the hardness of the fibroblastic cell is measured by proposed method and the effectiveness of the proposal technique is shown.
    No preview · Conference Paper · Sep 2011
  • [Show abstract] [Hide abstract]
    ABSTRACT: In the field of life science, such as regeneration medicine or cloning, the manipulation and analysis of cells is performed by researchers. However, in micro environments, manipulating objects by hand is often not feasible or practical. We have developed a two-fingered microhand, which will help to improve operation efficiency. Using the microhand, we can manipulate cells i.e., grab, rotate, carry, and so on - like when using chop sticks. The stiffness measurement of a cell is a key approach in single cell analysis techniques. It is important in indicating cell condition, because the stiffness of a cancer cell is lower than that of a normal cell as an example. In this paper, the pressure force caused in the process of cell deformation is measured via a micro force sensor attached to the root of micro glass needle. Our results point out that this can be one efficient measurement method for acquiring cell stiffness. The micro force sensor uses strain gauges to measure the strain of the glass needle so that we can find out the force generated on the micro force sensor indirectly. In this paper, two topics are discussed. One is for converting strain data to force data based on the force sensor model. The other refers to the experimental results about the stiffness measurement of the oocyte.
    No preview · Conference Paper · Jan 2011
  • [Show abstract] [Hide abstract]
    ABSTRACT: We develop an automated cell-cutting technique for cell cloning. Animal cells softened by the cytochalasin treatment are injected into a microfluidic chip. The microfluidic chip contains two orthogonal channels: one microchannel is wide, used to transport cells, and generates the cutting flow; the other is thin and used for aspiration, fixing, and stretching of the cell. The injected cell is aspirated and stretched in the thin microchannel. Simultaneously, the volumes of the cell before and after aspiration are calculated; the volumes are used to calculate the fluid flow required to aspirate half the volume of the cell into the thin microchannel. Finally, we apply a high-speed flow in the orthogonal microchannel to bisect the cell. This paper reports the cutting process, the cutting system, and the results of the experiment.
    No preview · Article · Jan 2011
  • [Show abstract] [Hide abstract]
    ABSTRACT: We fabricated a polydimethylsiloxane (PDMS)-based microwell plate (PDMS-MP) containing 100 microwells with a rounded bottom and examined whether it can be used for culture of individual in vitro fertilized (IVF) embryos or parthenogenetically activated zona-free embryos in cattle. In Experiment 1, we examined the in vitro developmental ability of IVF embryos cultured individually on PDMS-MP. After IVF, 20 embryos were transferred into 100 microl drops on PDMS-MP and cultured individually in each well of PDMS-MP (PDMS group). After 7 days of culture, the embryos in the PDMS group developed to the blastocyst stage at the same rate of those in the control group cultured in a group of 20 embryos without PDMS-MP. There were no differences in total number of cells and the ratio of inner cell mass to total cells between the PDMS and control groups. In Experiment 2, we examined the in vitro developmental ability of parthenogenetically activated zona-free bovine embryos cultured individually on PDMS-MP. The zona-free embryos were cultured individually in each well of a PDMS-MP or in each well produced by pressing a darning needle onto the bottom of a culture dish (WOW group). After 7 days of culture, the blastocyst formation rate and cell number of blastocysts in the PDMS group did not differ from those of the zona-intact embryos in the control group. Also, there were no differences in the blastocyst formation rate and cell number of blastocysts between the WOW and PDMS groups. These results suggest that the culture system using PDMS-MP is useful for individual embryos or zona-free embryos in cattle.
    No preview · Article · Aug 2010 · Journal of Reproduction and Development
  • Akihiko Ichikawa · Tamio Tanikawa · Satoshi Akagi · Kohtaro Ohba
    [Show abstract] [Hide abstract]
    ABSTRACT: We have developed an automated cell cutting and its nucleus detection technique for automated nucleus transplantation. Animal cells softened by cytochalasin treatment were injected into a microfluidic chip. The microfluidic chip contained 2 orthogonal channels: 1 microchannel was wide, was used to transport cells, and to generate the cutting flow; the other microchannel was thin and used for aspiration, fixing, and stretching of the cell. The injected cell was aspirated and stretched thin into the thin microchannel. Simultaneously, the volume of the cell before and after aspiration was calculated; this volume was used to calculate the fluid flow required to aspirate half the volume of the cell into the thin microchannel. Then, we applied a high-speed flow in the orthogonal microchannel to bisect the cell. Finally, we observed the nucleus of the cut cells to detect the non-nucleus cell. This paper reports the cutting and the detection process and the system, and result of the experiment.
    No preview · Conference Paper · Jan 2010
  • Akihiko Ichikawa · Tamio Tanikawa · Kohtaro Ohba
    [Show abstract] [Hide abstract]
    ABSTRACT: The purpose of our research work is to develop a multifunctional piezoelectric actuation mechanism for micro-manipulator using 3 degree of freedom actuation plate and expansion plate which its expansion rate and its character frequency can be adjusted by the number of the laminated hinge mechanism. It is important to downsizing of actuation mechanism along with the miniaturization of electronic circuit devices, moreover the making to high accuracy and integration of the actuator are also needed. The expansion mechanism is made by thin metal plates which have hinge mechanism. The expansion rate can be controlled by the number of the expansion plates. The expansion mechanism is small and useful to make micro-manipulator which can be set up on a microscope stage. This report shows a principle of the hinge mechanism, systems of micro-manipulator and result of the manipulation experiment.
    No preview · Article · Nov 2009

Publication Stats

287 Citations
26.72 Total Impact Points

Institutions

  • 2014
    • Meijo University
      Nagoya, Aichi, Japan
  • 2001-2013
    • Nagoya University
      • Department of Micro-Nano Systems Engineering
      Nagoya, Aichi, Japan
  • 2006-2011
    • National Institute of Advanced Industrial Science and Technology
      Tsukuba, Ibaraki, Japan
  • 2010
    • Japan Advanced Institute of Science and Technology
      KMQ, Ishikawa, Japan
  • 2008
    • Indore Institute of Science & Technology
      Indaur, Madhya Pradesh, India