Praneeth Ivan Joel Fnu, Md Tanim-Al Hassan, Timothy Yaroshuk, Yongling Ai, Hao Chen
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引用次数: 0
Abstract
Peptide/protein quantitation using mass spectrometry (MS) is advantageous due to its high sensitivity. Traditional absolute peptide quantitation methods rely on making calibration curves using peptide standards or isotope-labelled peptide standards, which are expensive and take time to synthesize. A method which can eliminate the need for using standards would be beneficial. Recently, we developed coulometric mass spectrometry (CMS) which can be used to quantify peptides that are oxidizable (e.g., those containing tyrosine or tryptophan), without using peptide standard. The method is based on electrochemical oxidation of peptides followed by MS measurement of the oxidation yield. However, it cannot be directly used to quantify peptides without oxidizable residues. To extend this method for quantifying peptides/proteins in general, in this study, we adopted a derivatization strategy, in which a target peptide is first tagged with an electroactive reagent such as monocarboxymethylene blue NHS ester (MCMB-NHS ester), followed with quantitation by CMS. To illustrate the power of this method, we have analyzed peptides MG and RPPGFSPFR. The quantification error was less than 5%. Using RPPGFSPFR as an example, the quantitation sensitivity of the technique was found to be 0.25 pmol. Furthermore, we also used the strategy to quantify proteins cytochrome C and β-casein with an error of 2–26 %.
期刊介绍:
The journal invites papers that advance the field of mass spectrometry by exploring fundamental aspects of ion processes using both the experimental and theoretical approaches, developing new instrumentation and experimental strategies for chemical analysis using mass spectrometry, developing new computational strategies for data interpretation and integration, reporting new applications of mass spectrometry and hyphenated techniques in biology, chemistry, geology, and physics.
Papers, in which standard mass spectrometry techniques are used for analysis will not be considered.
IJMS publishes full-length articles, short communications, reviews, and feature articles including young scientist features.