Bio-Rad Human MMP and TIMP Assays - Manual (Page 4)

Principle
Technology
The Bio-Plex ® multiplex system is built upon the three core elements of
xMAP technology:
n
Fluorescently dyed magnetic microspheres (also called beads),
each with a distinct color code or spectral address to permit
discrimination of individual tests within a multiplex suspension. This
allows simultaneous detection of up to 500 different molecules in a
single well of a 96-well microplate on the Bio-Plex
® 3D system, up to
100 different molecules on the Bio-Plex ® 200 system, and up to 50
different molecules on the Bio-Plex ® MAGPIX ™ system
n
A dedicated plate reader. The Bio-Plex 200 and Bio-Plex 3D systems
are flow cytometry–based instruments with two lasers and associated
optics to measure the different molecules bound to the surface of
the beads. In the Bio-Plex MAGPIX system, the sample is injected
into a chamber where the beads are imaged using LED and CCD
technology
n
A high-speed digital signal processor that efficiently manages the
fluorescence data
Assay Format
Bio-Plex Pro ™ assays are essentially immunoassays formatted on
magnetic beads. The assay principle is similar to that of a sandwich
ELISA (Figure 1). Capture antibodies directed against the desired
biomarker are covalently coupled to the beads. Coupled beads react
with the sample containing the biomarker of interest. After a series of
washes to remove unbound protein, a biotinylated detection antibody
is added to create a sandwich complex. The final detection complex is
formed with the addition of streptavidin-phycoerythrin (SA-PE) conjugate.
Phycoerythrin serves as a fluorescent indicator, or reporter.
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