Principle, Principle 2, Technology – Bio-Rad Bio-Plex Pro™ RBM Canine Kidney Toxicity Assays User Manual
Page 4: Assay format
2
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 types of molecules in a single well of
96-well microplate on the Bio-Plex
®
3D system, up to 100 different
types of molecules on the Bio-Plex
®
200 system, and up to 50 different
types of molecules on the Bio-Plex
®
MAGPIX
™
system
n
On the Bio-Plex 200 and Bio-Plex 3D systems, a dedicated flow
cytometer with two lasers and associated optics to measure the
different molecules bound to the surface of the beads. In the
Bio-Plex MAGPIX, the entire sample load volume 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
The Bio-Plex Pro
™
RBM kidney toxicity 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.