title: Implementation of tetra-poly(ethylene glycol) hydrogel with high mechanical strength into microfluidic device technology.
abstract: Hydrogels have several excellent characteristics suitable for biomedical use such as softness, biological inertness and solute permeability. Hence, integrating hydrogels into microfluidic devices is a promising approach for providing additional functions such as biocompatibility and porosity, to microfluidic devices. However, the poor mechanical strength of hydrogels has severely limited device design and fabrication. A tetra-poly(ethylene glycol) (tetra-PEG) hydrogel synthesized recently has high mechanical strength and is expected to overcome such a limitation. In this research, we have comprehensively studied the implementation of tetra-PEG gel into microfluidic device technology. First, the fabrication of tetra-PEG gel/PDMS hybrid microchannels was established by developing a simple and robust bonding technique. Second, some fundamental features of tetra-PEG gel/PDMS hybrid microchannels, particularly fluid flow and mass transfer, were studied. Finally, to demonstrate the unique application of tetra-PEG-gel-integrated microfluidic devices, the generation of patterned chemical modulation with the maximum concentration gradient: 10% per 20 μm in a hydrogel was performed. The techniques developed in this study are expected to provide fundamental and beneficial methods of developing various microfluidic devices for life science and biomedical applications.
authors.affiliation: Department of Bioengineering, School of Engineering, The University of Tokyo, 2-11-16, Yayoi, Bunkyo-ku, Tokyo, 113-8656, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Takehara
authors.affiliation: Center for Disease Biology and Integrative Medicine, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Nagaoka
authors.affiliation: Center for Disease Biology and Integrative Medicine, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Noguchi
authors.affiliation: Department of Bioengineering, School of Engineering, The University of Tokyo, 2-11-16, Yayoi, Bunkyo-ku, Tokyo, 113-8656, Japan.
authors.forename: Takanori
authors.initials: T
authors.lastname: Akagi
authors.affiliation: Department of Bioengineering, School of Engineering, The University of Tokyo, 2-11-16, Yayoi, Bunkyo-ku, Tokyo, 113-8656, Japan.
authors.forename: Takamasa
authors.initials: T
authors.lastname: Sakai
authors.affiliation: Department of Bioengineering, School of Engineering, The University of Tokyo, 2-11-16, Yayoi, Bunkyo-ku, Tokyo, 113-8656, Japan ; Center for Disease Biology and Integrative Medicine, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
authors.forename: Ung-Il
authors.initials: UI
authors.lastname: Chung
authors.affiliation: Center for Disease Biology and Integrative Medicine, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
authors.forename: Haruo
authors.initials: H
authors.lastname: Kasai
authors.affiliation: Department of Bioengineering, School of Engineering, The University of Tokyo, 2-11-16, Yayoi, Bunkyo-ku, Tokyo, 113-8656, Japan.
authors.forename: Takanori
authors.initials: T
authors.lastname: Ichiki