Bio-Rad Experion Protein Analysis Kits - Manual (Page 26)

5. Examine the % Total values for these peaks in both sample concentrations. Note that,
regardless of the total sample concentration, the percentage of total represented
remains the same.
Expected Performance for BGG in Test 2
Measurement Typical Results
% Total (Percentage determination)
Ligh-chain fragment 33–43% Total protein
Heavy-chain fragment 57–67% Total protein
If your results do not appear as they do in these examples, the most likely cause is
insufficient reducing conditions in the sample buffer. Ensure that reducing buffer (“R”) was
used to prepare samples and check that DTT was stored properly (at 4°C or reconstituted
at –20°C).
Percentage determination is a particularly simple method of protein of quantitation because
it does not rely on any internal standard. It is a highly reproducible qualitative method for
estimating protein levels and purity, and it is a good method for tracking sample quality
without relying on absolute concentrations.
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