Biomedical Engineering Reference
In-Depth Information
1
BIOMEDICAL MICROFLUIDICS AND
ELECTROKINETICS
Steve Wereley
Associate Professor, School of Mechanical Engineering,
Purdue University, West Lafayette, Indiana
Carl Meinhart
Associate Professor, Mechanical and Environmental
Engineering Department, University of California, Santa Barbara
Flow phenomena are of great importance in the study of biological systems: both natural
organisms and biomedical devices. Although scientists and engineers have an excellent
understanding of transport processes at large length scales, the study of transport proc-
esses at cellular length scales and smaller is just beginning. Considering the importance
of biological activities at and below the cellular level (see also this volume, Part III, chap-
ter 2.1, by Huang, Sultan, and Ingber), it is critical to understand the microfluidic envi-
ronment in which these processes occur and how we can manipulate them. Recent strides
in micrometer- and nanometer-scale diagnostic techniques have allowed exploration of
flow phenomena at length scales comparable to single cells, and even smaller. One of the
most useful means of manipulating fluids and suspended species such as cells, DNA, and
viruses is with electric fields. Electrokinetic phenomena are important at micron length
scales, and can be used to manipulate fluid and particle motion in microfluidic devices.
This chapter will briefly review the various methods of electrokinetic fluid and particle
manipulation, then review the recently developed microfluidic diagnostic processes
available for assessing flow behavior at micron length scales, and finally discuss in detail
advances in electrothermal and dielectrophoretic fluid and particle manipulation.
Address correspondence to: Steve Wereley, School of Mechanical Engineering, 585 Purdue Mall,
Purdue University, West Lafayette, IN 47907 (wereley@purdue.edu).
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