Quantification of transferrin in human serum using both QconCAT and synthetic internal standards

Published

September 27, 2013

Author(s)

Tyler A. Zimmerman, Meiyao M. Wang, Mark S. Lowenthal, Illarion V. Turko, Karen W. Phinney

Abstract

Transferrin, an iron transport protein, is a clinically-important biomarker in diseases such as iron-deficiency anemia. Current diagnostic methods for transferrin levels lack quantitative accuracy, suggesting the need for alternative approaches like LC-MS with isotope-labeled peptides as internal standards. Besides solid-phase synthesis, isotope-labeled peptides are also generated by a method called QconCAT where peptides are expressed from DNA in the presence of heavy isotope media. After evaluation of the expressed QconCAT, this study compares transferrin levels obtained by synthetic peptides versus QconCAT peptides as internal standards. Transferrin levels obtained by both internal standards give overlapping, or nearly overlapping, uncertainty values near ≈200 mg/dL of transferrin in human serum. Close agreement between the two methods suggests that the quantitative values are reasonable. Using QconCAT and synthetic peptides in parallel gives a refined focus on method development, and the resulting methods should be applicable to other clinically- relevant proteins.

Citation

Analytical Chemistry

Volume

85

Pub Type

Journals

Download Paper

DOI Link

Keywords

Transferrin, Peptides, Proteins, QconCAT, Mass Spectrometry, Liquid Chromatography, Quantification, Quantitation, Human Serum

Citation

Zimmerman, T. , Wang, M. , Lowenthal, M. , Turko, I. and Phinney, K. (2013), Quantification of transferrin in human serum using both QconCAT and synthetic internal standards, Analytical Chemistry, [online], https://doi.org/10.1021/ac402326v (Accessed March 4, 2025)