omation mbers - Society for Laboratory Automation and Screening

12:00 pm Wednesday, February 4 High Throughput Screening – Analytical Room A2
Rebecca Zangmeister
National Institute of Standards and Technology
100 Bureau Drive, MS 8362
Gaithersburg, Maryland 20899
razang@nist.gov
Integration of Hydrogel Based Bioassays Into Microfluidic Channels
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Co-Author(s)
Michael J. Tarlov
We previously reported a method for immobilizing single-stranded DNA (ss-DNA) probe molecules in
polyacrylamide hydrogels within plastic microfluidic channels. Low concentrations of fluorescent-tagged ss-DNA
targets hybridize with immobilized probes and are detected in the hydrogels. We aim to couple two novel bioassays
with this basic technology. The first is a diagnostic DNA assay that does not require pre-labeling of the target strand
prior to analysis. The assay is based on the displacement of a short sacrificial fluorescent-tagged indicator oligomer
by a longer untagged target sequence as it is electrophoresed through a DNA-containing hydrogel plug immobilized
in a microfluidic channel. The distinct advantage of this assay is the ability to detect non-labeled target DNA. The
second is a lead sensitive assay, based on the response of catalytic DNA to Pb(II) ions. Our goal is to immobilize
the enzyme strand sequence of the catalytic DNA duplex in a hydrogel plug immobilized in a microfluidic channel.
Fluorescently tagged substrate strands are electrophoresed into the hydrogel plug where they hybridize with the
immobilized enzyme strands, forming the catalytic DNA system. Electrophoretic migration of Pb(II) ions through the
hydrogel plug results in catalytic cleavage of the substrate strand and release of the fluorescent-tagged sequence
fragment that is detected in a second capture plug. Both assays feature enhanced sensitivity due to high loading of
DNA probes in the hydrogel plugs, the spatially confined, directed mass transfer characteristics of the microfluidic
channels, and the inherently low fluorescent background of the hydrogels.
3:30 pm Wednesday, February 4 High Throughput Screening – Data Analysis and QC Room A2
Anthony Carlo
Pfizer
Eastern Point Road
Groton, Connecticut 06340
Anthony_A_Carlo@groton.pfizer.com
Evotec µHTS Data Analysis – Making the Most of the Multiparametric Readout
This presentation will discuss our efforts towards improving hit detection in lead discovery by increasing the
confidence of identifying true positives verses false positives/negatives in primary HTS data. Towards this goal, the
talk will focus on the use of single molecule fluorescence detection provided by the Evotec OAI µHTS platform,
which provides multi-parametric data readout from miniaturized assay formats and how this information is
processed. These techniques will be applied across multiple HTS assays.