Quantification of proteins and metabolites by mass spectrometry without isotopic labeling or spiked standards.
A new method is presented for quantifying proteomic and metabolomic profile data by liquid chromatography-mass spectrometry (LC-MS) with electrospray ionization. This biotechnology provides differential expression measurements and enables the discovery of biological markers (biomarkers). Work presented here uses human serum but is applicable to any fluid or tissue. The approach relies on linearity of signal versus molecular concentration and reproducibility of sample processing. There is no use of isotopic labeling or chemically similar standard materials. Linear standard curves are reported for a variety of compounds introduced into human serum. As a measure of analytical reproducibility for proteome and metabolome sampling, median coefficients of variation of 25.7 and 23.8%, respectively, were determined for approximately 3400 molecular ions (not counting their numerous isotopes) from 25 independently processed human serum samples, corresponding to a total of 85000 individual molecular ion measurements.
Wang
Weixun
W
SurroMed, Inc., 2375 Garcia Avenue, Mountain View, California 94043, USA.
Zhou
Haihong
H
Lin
Hua
H
Roy
Sushmita
S
Shaler
Thomas A
TA
Hill
Lander R
LR
Norton
Scott
S
Kumar
Praveen
P
Anderle
Markus
M
Becker
Christopher H
CH
D006801:Humans; D007553:Isotope Labeling; D013058:Mass Spectrometry / Q000379:methods*; D011506:Proteins / Q000032:analysis*; D012015:Reference Standards; D015203:Reproducibility of Results
D011506:Proteins