World’s thinnest all-glass flexible microfluidic chip

A new fabrication method developed by a research team at RIKEN enables the fabrication of the world’s thinnest 100%-glass-based flexible microfluidic chip. The study led by Yo Tanaka, a unit leader of the Laboratory for Integrated Biodevice Quantitative Biology Center (QBiC) RIKEN, and Yaxiaer Yalikun, a postdoctoral researcher, was published in Lab on a Chip on May 26, 2016. The research team aimed to establish a new glass processing technique for next-generation microfluidic chips. This research was funded by the ImPACT program “Turning Serendipity into Planned Happenstance” led by Keisuke Goda, Program Manager, and directed by the Council for Science, Technology and Innovation in the Cabinet Office, Government of Japan.

While microfluidic devices made from glass are chemically stable against organic solvents and gas, conventional fabrication methods for preparing hard glass materials are unsuitable for ultra-thin glass sheets. Because of its fragility and heavier weight compared to other flexible materials, glass was considered unsuitable for applications, which require extremely thin, lightweight, flexible, and high pressure-proof attributes. The research team focused on a commercially available ultra-thin glass sheet, which allows the minimum thickness to be 4 micrometers. However, thin glass was generally difficult to handle and unsuitable for the conventional fabrication method because of its extreme flexibility.

The research team used a femtosecond laser to cut an ultra-thin glass sheet and bond it with a non-fabricated glass sheet. This is an effective process to fabricate a next-generation glass microfluidic chip. The laser technology, which was jointly developed with a research team led by Takanori Iino, a project assistant professor of Graduate School of Nara Institute of Science and Technology, was applied to the fabrication of the ultra-thin and flexible glass device.

The developed technology is expected to be applied to a variety of fields such as personalized medicine, biological science, and energy generation devices.