Bio-Rad Experion Protein Analysis Kits - Manual (Page 32)

How Experion Software Analyzes Proteins
Data Presentation
As the photodiode detects fluorescent signals from the dye-protein-LDS complexes,
Experion software converts the signal into an electropherogram (a plot of fluorescence vs.
time). Experion Pro260 electropherograms generally have the following features:
Sample peak(s) –– signal(s) generated by the sample protein(s)
System peaks –– cluster of signals generated by fluorescent detergent micelles. The system
peaks are not considered in the quantitative concentration estimation
Upper and lower marker –– signals generated by the internal upper (260 kD) and lower
(1.2 kD) markers, which are included in the sample buffer and used to normalize the
separation of proteins across all wells in the chips. The upper marker is also used as an
internal standard for relative quantitation (see below). For each lane, comparison of the area
of this peak with the area of every detected peak allows estimation of relative concentration
Electropherogram generated by Experion Pro260 analysis of bovine gg-globulin (BGG). The relative
positions of the lower marker, system peaks, sample peak (BGG), and upper marker are shown.
Once separation occurs, these data are then converted into a densitometric, gel-like image,
or virtual gel. Each lane in the virtual gel corresponds to a different sample. The sample and
system peaks and upper and lower markers seen in the electropherogram also appear in
the virtual gel.
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