Alternate Soaking Technique for Micropatterning Alginate Hydrogels on Wettability-patterned Substrates

• Published in: Journal of Oleo Science Vol. 68; no. 1; pp. 53 - 60
• Main Authors: Watanabe, Satoshi, Tominaga, Taiga, Matsumoto, Mutsuyoshi
• Format: Journal Article
• Language: English
• Published: Japan Japan Oil Chemists' Society 2019; Japan Science and Technology Agency
• Subjects: Actuators; alginate hydrogel; Alginates - chemistry; alternate soaking; Cations, Divalent - chemistry; Crosslinking; Divalent cations; divalent metal; Film thickness; Gels; Glass - chemistry; Glass plates; Hydrogels; Hydrogels - chemical synthesis; Hydrogels - chemistry; Hydrogen-Ion Concentration; Hydrophobic and Hydrophilic Interactions; Metals, Alkaline Earth - chemistry; Micropatterning; Precursors; Self-assembled monolayers; Self-assembly; Soaking; Sodium alginate; Substrates; Wettability; wettability-patterned substrate; divalent metal; wettability-patterned substrate; alternate soaking; alginate hydrogel
• ISSN: 1345-8957; 1347-3352
• DOI: 10.5650/jos.ess18166

Techniques for patterning hydrogels are important for fabrication of cell culture, analytical, and actuator devices at the micro- and nanometer length scales. In this study, we fabricated alginate hydrogels cross-linked by divalent cations on wettability-patterned substrates by alternate soaking of precursor solutions of sodium alginate and divalent cations. The wettability-patterned substrates were fabricated on hydrophilic glass plates modified with hydrophobic self-assembled monolayers of hexamethyldisilazane followed by exposure to an ultraviolet/ozone atmosphere through a metal mask. The film thickness of alginate gels with a width and length of 0.1 and 4 mm were tuned stepwise from 30 nm to 200 nm by adjusting the precursor conditions, including the pH, type of divalent metal ions, and sodium alginate concentration, and the alternate soaking conditions, including the dipping/withdrawal speed and number of alternate soaking cycles. This technique can be applied to other functional gels and will contribute to fabrication of hydrogel devices at the micro- and nanometer scales in the future.