omation mbers - Society for Laboratory Automation and Screening

3:30 pm Tuesday, February 3 Microfluidics Room A4
Carl Meinhart
University of California, Santa Barbara
Santa Barbara, California 93106
meinhart@engineering.ucsb.edu
Analysis of Microscale Transport for BioMEMS
During recent years there has been significant development in the field of microfluidics and its application to
BioMEMS devices. The scalability and sensitivity of BioMEMS make them well suited for manipulating and
analyzing macromolecules. Microfluidics plays a key role in the transport processes inside these devices,
which include advection, Brownian motion, electrokinetic phenomena, and surface-dominated forces. Recent
developments at UCSB of a fully-integrated tunable laser cavity sensor for optical immunoassays will be
presented. This device incorporates a pair of Distributed Bragg Reflector (DBR) lasers to sense specific antigen/
antibody binding events that occur in the evanescent field of the laser cavity. The binding event modifies the
modal index of the laser through coupling of the evanescent field. The modal index can be detected theoretically
to within a resolution of n ~ 10 -7 . Dielectrophoresis (DEP) is proposed as a method for manipulating the antigen
concentration fields, thereby enhancing the sensitivity of the device. The length scales of microfluidic devices
typically range between 100 – 102 microns. In order to make full use of the physical phenomena at this scale and
to understand how these devices function, accurate non-intrusive diagnostic techniques are required. To this end,
a micron-resolution Particle Image Velocimetry (micro-PIV) system has been developed to measure velocity-vector
fields with order one-micron spatial resolution. The resolution of the PIV system is demonstrated by measuring the
flow field in a 30 x 300 micron channel. By overlapping the interrogation spots by 50%, a velocity-vector spacing
of 450 nm is achieved. Surprisingly, the velocity measurements indicate that the well-accepted no-slip boundary
condition may not be valid for hydrophobic/hydrophilic boundaries at the microscale. These results represent the
first direct experimental measurement of this phenomenon.
4:00 pm Tuesday, February 3 Microfluidics Room A4
Jill Baker
Caliper Technologies Corp.
605 Fairchild Drive
Mountain View, California 94043
jill.baker@calipertech.com
Single Molecule Amplification in a Continuous Flow LabChip Device
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Co-Author(s)
Michelle L. Strachan, Ken Swartz,
Yevgeny Yurkovetsky, Aaron Rulison,
Carlton Brooks, Anne R. Kopf-Sill
New biological and diagnostic markers are rapidly emerging from genomic studies that can provide meaningful
insights into a patient’s health. In many cases, these involve the analysis of nucleic acids. For complex genomes,
the polymerase chain reaction (PCR) is often used to prepare the sample for sequence-specific or allele-specific
interrogation. The advantages of “lab-on-a-chip” devices, i.e., miniaturization, integration and automation, would
be useful additions to the diagnostician’s arsenal as they produce better data quality, reduced cost, and improved
ease-of-use features by comparison to conventional technology. An emerging need in nucleic acids diagnostics
is detecting rare mutant molecules from conveniently obtained patient specimens that reflect the presence of
neoplastic tissue. We have developed an automated, microfluidic system capable of analyzing single molecules
by PCR amplification and TaqMan genotyping. The integrated features of this system make it a candidate format
for high throughput, diagnostic laboratory settings. The system is unique in several respects. One, the system
integrates reaction assembly, thermal cycling and fluorescence detection on one chip. This allows different
samples to be tested one after another in an automated way, all at nanoliter scale. Two, the chip we have created
uses our sip-and-split design and has eight channels in which eight different loci can be amplified at one time
for each sample. In addition, we have recently configured the system to continuously amplify and detect single
molecules of DNA.
PODIUM ABSTRACTS