Please
tell us a little about your research and educational background. What
first interested you in microfluidics research?
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"Prior
to our work, micromechanical valves required
significant effort to fabricate, and the joke in
the field was 'one valve, one Ph.D. thesis'." |
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I was trained in physics and mathematics, then became interested
in the interface between biology and physics. Working there led me
naturally into technology development. As I learned how biology was
practiced, it seemed that there must be less labor-intensive ways of
getting the answers one is interested in. Most of the practical
bench work in biology is pipetting, or fluid manipulation, so I
began to get more and more interested in fluidic (and therefore
microfluidic) automation.
Your
most-cited paper in our database is the 2000 Science article,
"Monolithic microfabricated valves and pumps by multilayer soft
lithography." Would you please walk our readers through this paper—what
were your goals, what did you find, etc.?
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Dr. Stephen
Quake's most-cited paper with 433 cites to date: |
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Unger
MA, et al., "Monolithic monofabricated valves
and pumps by multilayer soft lithography,"
Science 288(5463): 113-6, 7 April 2000. 443
cites.
Source:
Essential Science Indicators. |
|
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Our goal was to build a simple and easy-to-fabricate
micromechanical valve. Prior to our work, micromechanical valves
required significant effort to fabricate, and the joke in the field
was "one valve, one Ph.D. thesis." We figured out how to make a
mechanical valve using only elastomeric materials—this valve was
easy to fabricate and use. Two years later we published a paper
describing the microfluidic large-scale integration (mLSI)—the first
time anyone had been able to fabricate hundreds and even thousands
of valves on a single chip. This work used essentially the same
valve-fabrication technology described in our 2000 Science
article.
How
have you built on this work since that 2000 paper?
We have gone on to explore numerous biological applications of
mLSI, including structural biology, single cell analysis,
bioreactors for synthetic biology, precision measurements of binding
energies for systems biology, and so forth.
What
other papers in your canon, either within or outside of the confines of
our analysis, would you say possess particular significance?
The 2002 Science paper on mLSI, "Microfluidic large-scale
integration" (Thorsen T, Maerkl SJ, Quake SR, 298[5593]: 580-4, 18
October 2002), is also highly cited. Todd Squires and I tried to
write a comprehensive review of microfluid physics that came out in
Reviews in Modern Physics a couple years ago—"Microfluidics:
fluid physics at the nanoliter scale," (77[3]: 977-1026, July 2005).
Jessica Melin and I wrote a review outlining design rules for mLSI
that came out this year ("Microfluidic large-scale integration: the
evolution of design rules for biological automation," Annual
Review of Biophysics and Biomolecular Structure 36: 213-31, June
2007).
What
should the "take-away lesson" about your work be for the general public?
That it is now possible to create miniaturized plumbing
automation that rivals the 1970s-era integrated circuit in its
complexity. Many biological applications are benefiting.
Stephen Quake, Ph.D.
Stanford University
Palo Alto, CA, USA
n
the interview below, we talk with Dr. Stephen Quake about
his highly cited work in microfluidics. According to our
Special Topics analysis of the field, Dr. Quake’s work ranks
at #2, with 35 papers cited a total of 2,184 times. In