Hostname: page-component-586b7cd67f-t8hqh Total loading time: 0 Render date: 2024-11-24T06:46:54.324Z Has data issue: false hasContentIssue false

Scaling Electrowetting with Printed Circuit Boards for Large Area Droplet Manipulation

Published online by Cambridge University Press:  04 April 2018

Udayan Umapathi*
Affiliation:
MIT Media Lab, Cambridge, MA, U.S.A
Samantha Chin
Affiliation:
Wellesley College, MA, U.S.A
Patrick Shin
Affiliation:
MIT Media Lab, Cambridge, MA, U.S.A
Dimitris Koutentakis
Affiliation:
MIT Media Lab, Cambridge, MA, U.S.A
Hiroshi Ishii
Affiliation:
MIT Media Lab, Cambridge, MA, U.S.A
*

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Droplet based microfluidics (digital microfluidics) with Electrowetting on dielectric (EWOD) has gained popularity with the promise of being technology for a true lab-on-chip device with applications spanning across assays/library prep, next-gen sequencing and point-of-care diagnostics. Most electrowetting device architecture are linear electrode arrays with a shared path for droplets, imposing serious limitations -- cross contamination and limited number of parallel operations. Our work is in addressing these issues through large 2D grid arrays with direct addressability providing flexible programmability.

Scaling electrowetting to larger arrays still remains a challenge due to complex and expensive cleanroom fabrication of microfluidic devices. We take the approach of using inexpensive PCB manufacturing, investigate challenges and solutions for scaling electrowetting to large area droplet manipulation. PCB manufactured electrowetting arrays impose many challenges due to the irregularities from process and materials used. These challenges generally relate to preparing the surface that interfaces with droplets -- a dielectric material on the electrodes and the top most hydrophobic coating that interfaces with the droplets. A requirement for robust droplet manipulation with EWOD is thin (<10um) hydrophobic dielectric material which does not break down at droplet actuation voltages (AC/DC, 60V to 200V) and has a no droplet pinning. For this, we engineered materials specifically for large area PCBs.

Traditionally, digital microfluidic devices sandwich droplets between two plates and have focussed on sub-microliter droplet volumes. In our approach, droplets are on an open surface with which we are able to manipulate droplets in microliter and milliliter volumes. With milliliter droplet manipulation ability on our electrowetting device, we demonstrate “digital millifluidics”. Finally, we report the performance of our device and to motivate the need for large open arrays we show an example of running multiple parallel biological experiments.

Type
Articles
Copyright
Copyright © Materials Research Society 2018 

References

REFERENCES

Lippmann, Gabriel, PhD. Thesis, Gauthier Villars, 1875.Google Scholar
Liquavista. Available at: https://www.liquavista.com/ (accessed 20 November 2017).Google Scholar
Beni, G. and Hackwood, S., Applied Physics Letters 38(4), 207209 (1981).Google Scholar
Pollack, M.G., Fair, R.B., and Shenderov, A.D., Applied Physics Letters 77(11), 17251726 (2000).Google Scholar
Mei, N., Seale, B., Ng, A.H., Wheeler, A.R., and Oleschuk, R., Analytical Chemistry, 86(16), 84668472 (2014).Google Scholar
Moon, H., Cho, S.K., Garrell, R.L., and Kim, C.J.C., Journal of applied physics, 92(7), 40804087 (2002).Google Scholar
Wilson, P.W., Lu, W., Xu, H., Kim, P., Kreder, M. J., Alvarenga, J., and Aizenberg, J., Physical Chemistry Chemical Physics, 15(2), 581585 (2013).Google Scholar
Seyrat, E. and Hayes, R.A., Journal of Applied Physics, 90(3), 13831386 (2001).Google Scholar
Cooney, C.G., Chen, C.Y., Emerling, M.R., Nadim, A. and Sterling, J.D.. Microfluidics and Nanofluidics, 2(5), 435446 (2006).Google Scholar
Jebrail, M.L., Wheeler, A.R.. Current opinion in chemical biology, 14(5), 574–81 (2010).Google Scholar
Alistar, M., Gaudenz, U.. Bioengineering, 4(2), 45(2017).Google Scholar
Rackus, D.G., de Campos, R.P., Chan, C., Karcz, M.M., Seale, B., Narahari, T., Dixon, C., Chamberlain, M.D., Wheeler, A.R.. Lab on a Chip (2017).Google Scholar
Chen, W., Fadeev, A.Y., Hsieh, M.C., Öner, D., Youngblood, J., and McCarthy, T.J.. Langmuir, 15(10), 33953399 (1999).Google Scholar
De Gennes, P.G.. Reviews of modern physics, 57(3), 827 (1985).Google Scholar
Walker, S.W., Shapiro, B., Nochetto, R.H.. Physics of Fluids. 21(10), 102103 (2009).Google Scholar
Verheijen, H. J. I. and Prins, M. W. J.. Langmuir, 15(20), 66166620 (1999).Google Scholar