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Cited by 398

The DOI matches its Crossref record; 22 of the 22 references it cites were found in a registry or an index.

Quantification of C‐reactive protein in the serum of patients with rheumatoid arthritis using multiple reaction monitoring mass spectrometry and 13C‐labeled peptide standards

Kuhn, Eric, Wu, Jiang, Karl, Johann, Liao, Hua, Zolg, Werner, Guild, Brad·2004·PROTEOMICS

Abstract

A general method for the quantification of proteins in human serum was developed using mass spectrometry (MS) and stable isotope‐labeled synthetic peptides as internal standards. Using this approach, C‐reactive protein (CRP), a diagnostic marker of rheumatoid arthritis (RA), was detected in serum samples taken from patients with either erosive or nonerosive RA and compared to healthy individuals. Small volumes of serum samples were enriched for low‐abundance proteins through the selective removal of human serum albumin (HSA), immunoglobulin G (IgG), and haptoglobin. After depletion of abundant proteins, the complexity of the protein mixture was further simplified using size exclusion chromatography (SEC) to fractionate denatured proteins into discrete molecular weight ranges. Fractions of interest containing CRP, Mr = 25 000, were pooled, digested with trypsin, and then fixed quantities of the synthetic peptides were added to the mixture. The mixture of tryptic peptides was subsequently analyzed by nanoflow chromatography‐tandem MS (nanoLC‐MS/MS) using multiple‐reaction monitoring (MRM) on a triple quadrupole mass spectrometer (TQ‐MS). The ratio of transition ions derived from the endogenous and isotope‐labeled peptides provided a quantitative measure of CRP in the original samples as assessed by independent measurement of CRP in the same patient samples using an immunoassay. The use of isotope‐labeled synthetic peptides and MRM is a powerful analytical method for the prescreening of candidate protein biomarkers in human serum prior to antibody and immunoassay development.

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Metadata

Authors
Kuhn, E., Wu, J., Karl, J., Liao, H., Zolg, W., & Guild, B.
Venue
PROTEOMICS
Publisher
Wiley
Published
2004-03-23
Volume
4
Issue
4
Pages
1175-1186
ISSN
  • 1615-9853 (ISSN-L)
  • 1615-9861
OpenAlex
W2062203307
Cited by
398
References
22
FWCI
8.45
Type
journal article
Language
en
Open access
closed

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CoChat. (2026). Citation check: Quantification of C‐reactive protein in the serum of patients with rheumatoid arthritis using multiple reaction monitoring mass spectrometry and 13C‐labeled peptide standards. https://app.cochat.ai/papers/10.1002/pmic.200300670
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Kuhn, E., Wu, J., Karl, J., Liao, H., Zolg, W., & Guild, B. (2004). Quantification of C‐reactive protein in the serum of patients with rheumatoid arthritis using multiple reaction monitoring mass spectrometry and 13C‐labeled peptide standards. PROTEOMICS. https://doi.org/10.1002/pmic.200300670

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