Abstract
High-throughput microarray
analyses require digitized images in
order to convert the signal intensity
to numerical values. To acquire the
images, laser scanners are usually
used for fluorescent signal detection.
However, such microarray scanners
have a limited number of excitation
wavelengths, take minutes to scan a
slide, and are expensive. In standard
transcriptional array configurations,
most study designs use relatively
few samples against many probes,
so only a small number of scans are
necessary to complete the digital
image acquisition for an experimental
set. However, other microarray-based
procedures may be more impacted by
the limitations of dedicated microarray
scanners. For instance, scanning is a
major rate-limiting step when using
high-density reverse-phase protein
lysate microarrays (RPA) (Reference
1 and Figure 1A), which we have
previously described as a method to
perform proteomic profiling of many
protein species across many samples.
Because RPA signal detection employs
a specific primary antibody followed
by the catalyzed signal amplification
colorimetric detection system (CSA;
DakoCytomation, Carpinteria, CA,
USA), whose final product is the
dark-colored stain diaminobenzodine
(DAB), signals can be obtained using
the reflective mode of an ordinary
optical flatbed scanner. Hence, we have
been using optical flatbed scanners
because of their fast scanning, relatively
compact file size, and wide availability.
However, there are several issues to be
considered when using these scanners
for quantitative applications.
Close Window