Activity

2025

[Papers where our lab members played a leading role]

  1. Takashi Kotani, Takehito Hananouchi, Shinji Sakai, Enhancing visible light-induced 3D bioprinting: alternating extruded support materials for bioink gelation, Biomedical Materials, 20, 035005 (2025) [DOI:10.1088/1748-605X/adc0d6].
    We proposed a method in which a support material containing SPS and a bioink containing a polymer with phenolic hydroxyl groups (HA-Ph) and a ruthenium complex ([Ru(bpy)3]²⁺) are alternately extruded, promoting gelation under visible light, and demonstrated its effectiveness. This was the result of a collaborative study with Professor Hananouchi from Hiroshima University.
  2. Ryotaro Kazama, Satoshi Fujita, Shinji Sakai, Cell Dome-Based Transfection Array for Non-adherent Suspension Cells, Biochemical Engineering Journal, 213, 109554 (2025) [DOI:10.1016/j.bej.2024.109554].
    This paper reports that our original technology, Cell Dome, enables efficient gene delivery to non-adherent cells that proliferate without attaching to the substrate. This was the result of a collaborative study with Professor Fujita from AIST (Osaka University Photonics Center).
  3. Mitsuyuki Hidaka, Shinji Sakai, Photo- and Schiff Base-Crosslinkable Chitosan/Oxidized Glucomannan Composite Hydrogel for 3D Bioprinting, Polysaccharides, 6, 19 (2025) [DOI:10.3390/polysaccharides6010019].
    This study developed a composite hydrogel of phenolic hydroxyl group-introduced chitosan and oxidized glucomannan by combining Schiff base formation and visible light-induced phenol crosslinking. The dual crosslinking improved printability, shape fidelity, antibacterial properties, and cytocompatibility, enabling the fabrication of well-defined 3D structures using low concentrations of crosslinking agents while maintaining good biocompatibility.
  4. Ryota Goto, Masahiro Terasawa, Masaru Kojima, Koichi Matsuda, Kaoru Nishiura, Shinji Sakai, Synthesis and application of phenol-grafted rhamnan sulfate for 3D bioprinting, Journal of Biomaterials Science: Polymer Edition, in press.[DOI:10.1080/09205063.2024.2427499].
    This study demonstrated that rhamnan sulfate, a sulfated polysaccharide derived from seaweed, can be chemically modified and used as a promising ink material for 3D bioprinting.

2024

  1. Ryotaro Kazama, Satoshi Fujita, Shinji Sakai, Shinji Sakai, Cell Dome-Based Transfection Array for Non-adherent Suspension Cells, Biochemical Engineering Journal, 213, January 2025, 109554 (2024). DOI:10.1016/j.bej.2024.109554].
    This paper reports on our Cell Dome technology, which enables efficient gene introduction to non-adherent cells that proliferate without adhering to the substrate. This is a collaborative work with Dr. Fujita from AIST (Osaka Photonics Center).
  2. Ayari Miyawaki, Shinji Sakai, Immobilization of laccases on mechanically ground silk fibroin nanofibers for enhanced stability, International Journal of Biological Macromolecules, 282 (1), 136745 (2024).[DOI:10.1016/j.ijbiomac.2024.136745].
    The paper demonstrates that silk nanofibers obtained by mechanically grinding silk fibers contribute to enhancing the stability of laccase when used as an immobilization carrier, allowing long-term use as a catalytic immobilization membrane in continuous reactors.
  3. Colin Zhang, Kelum Chamara Manoj Lakmal Elvitigala, Wildan Mubarok, Yasunori Okano, Shinji Sakai, Machine learning-based prediction and optimization framework for as-extruded cell viability in extrusion-based 3D bioprinting, Virtual and Physical Prototyping, 19(1), e2400330 (2024).[DOI:10.1080/17452759.2024.2400330].
    This research demonstrates the capability of predicting the load exerted on various types of cells within inks flowing through the nozzle during bioprinting and the subsequent reduction in viability, achieved through machine learning. This study was conducted in collaboration with Dr. Okano.
  4. Ryota Goto, Shinji Sakai, Cédric Delattre, Emmanuel Petit, Redouan El Boutachfaiti, Masaki Nakahata, Enzymatically cross-linkable sulfated bacterial polyglucuronic acid as an affinity-based carrier of FGF-2 for therapeutic angiogenesis, Journal of Bioscience and Bioengineering, 138 (6), 541-547 (2024).[DOI:10.1016/j.jbiosc.2024.08.011].
    This study, conducted in collaboration with a French research group, involves the development of an angiogenesis-promoting gel by chemically modifying polyglucuronic acid with sulfate groups to enhance its affinity with the cytokine bFGF and cross-linking it enzymatically.
  5. Mitsuyuki Hidaka, Masaru Kojima, Shinji Sakai, Micromixer driven by bubble-induced acoustic microstreaming for multi-ink 3D bioprinting, Lab on a Chip, 24, 4571-4580 (2024).[DOI:10.1039/D4LC00552J].
    This paper details the development of a 3D bioprinting nozzle equipped with a micromixer that stirs using bubbles oscillated by sound waves, an innovation by Hidaka. The method is slightly noisy when operating (earplugs solve this issue), and cell viability is not compromised.
  6. Wildan Mubarok, Kelum Chamara Manoj Lakmal Elvitigala, Hiroto Nakaya, Tomoki Hotta, Shinji Sakai, Cell cycle modulation through physical confinement in micrometer-thick hydrogel sheaths, Langmuir, 40 (35), 18717-18726 (2024).[DOI:10.1021/acs.langmuir.4c02434].
    This study reports on how the cell cycle is affected by a micrometer-thick gel membrane formed on the cell surface via peroxidase enzymatic reaction. This research, initiated by Hotta during his master’s studies, was further developed by Wildan, Kelum, and Nakaya.
  7. Mitsuyuki Hidaka, Masaru Kojima, Colin Zhang, Yasunori Okano, Shinji Sakai, Experimental and Numerical Approaches for Optimizing Conjunction Area Design to Enhance Switching Efficiency in Single-Nozzle Multi-Ink Bioprinting Systems, International Journal of Bioprinting, 10 (5), 4091 (2024).[DOI:10.36922/ijb.4091].
    This paper presents research on the design of nozzles for multi-ink 3D bioprinting, aiming to enhance ink switching within a single nozzle using experimental methods and simulations.
  8. Masaki Nakahata, Ai Sumiya, Yuka Ikemoto, Takashi Nakamura, Anastasia Dudin, Julius Schwieger, Akihisa Yamamoto, Shinji Sakai, Stefan Kaufmann, Motomu Tanaka, Hyperconfined Bio-Inspired Polymers in Integrative Flow-Through Systems for Highly Selective Removal of Heavy Metal Ions, Nature Communications, 15(1) 5824 (2024)[DOI:10.1038/s41467-024-49869-8].
    This paper discusses the development of a new polymer material inspired by proteins that selectively capture heavy metal ions in plants. The material achieves enhanced ion capture efficiency through ultra-high density and is applied to flow-through water purification systems.
  9. Kelum Chamara Manoj Lakmal Elvitigala, Wildan Mubarok, Shinji Sakai, Hydrogels with ultrasound-treated hyaluronic acid regulate CD44-mediated angiogenic potential of human vascular endothelial cells in vitro, Biomolecules, 14 (5), 604 (2024)[DOI:10.3390/biom14050604].
    This study shows that low-molecular-weight hyaluronic acid with phenolic hydroxyl groups introduced through ultrasound treatment controls capillary-like network formation mediated by CD44 expression on the surface of vascular cells.

[Review article etc...]

  1. Thaaranni Bashkeran, Shinji Sakai, Retno Wahyu Nurhayati, Minh Hong Nguyen, Wildan Mubarok, Ryota Goto, Dinda Shezaria Hardy Lubis, Auzan Luthfi, Masrina Mohd Nadzirm, Microbial Exopolysaccharides Production and Applications (Edited By Shashi Kant Bhatia, Parmjit Singh Panesar, Sanjeet Mehariya, CRC Press) [DOI: 10.1201/9781003342687], Chapter 4: Biomedical applications of exopolysaccharides
    An explanation of the biomedical applications of microbial exopolysaccharides secreted by microorganisms.
  2. Ayari Miyawaki, Shinji Sakai, Bioprinting using enzyme-gelling ink, Japanese Society of Imaging Science and Technology, Vol. 63, No. 4, 2024 p. 388-396　[DOI: 10.11370/isj.63.388],
    An explanation of 3D bioprinting using enzyme-gelling ink.