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bioRxiv · 10.1101/2025.02.24.639845

Proteome-wide multipoint internal calibration curves for mass spectrometry-based quantitative proteomics

Chiva, C.·Elhamraoui, Z.·Morales-Sanfrutos, J.·Pastor, O.·Sabido, E.
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Abstract

Mass spectrometry (MS)-based proteomics is known for its high accuracy in quantifying peptides and proteins using various calibration strategies, including internal and external calibration curves. While external multi-point calibration curves are created from serial dilutions, they often fail to account for sample-specific matrix effects. In contrast, internal calibration curves account for sample matrix but face scalability and cost challenges for whole proteome analyses. In this manuscript we present a novel TMT-based multipoint internal calibration curve strategy, referred to as TMTCal, which enables the generation of internal calibration curves for all peptides identified within a proteome within a single experiment. We applied this strategy to human ovarian cancer cells to evaluate the linear quantitative responses of all the identified peptides and reveal the significant proteome changes associated with cisplatin treatment.

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Chiva, C., Elhamraoui, Z., Morales-Sanfrutos, J., Pastor, O., Sabido, E.. 2025-02-28. Proteome-wide multipoint internal calibration curves for mass spectrometry-based quantitative proteomics. https://doi.org/10.1101/2025.02.24.639845

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