使用高分辨MRM对人血清中的目标蛋白质定量

　　简介：In this presentation, we demonstrate the TSQ Quantum Ultra mass spectrometer’s unparalleled capability for highly sensitive and accurate multiple protein quantitation from human serum by using high resolution multiple selected reaction monitoring (h-mSRM). An h-mSRM assay was developed for detecting 53 targeted proteins in human serum by using both unit mass resolution and high resolution (0.2 FWHM) for the Q1 quadrupole. The sensitivity, reproducibility, dynamic range and overall performance advantages of h-mSRM assays were evaluated. Additionally, a specific h-mSRM assay was developed for detecting a known biomarker (IL-6) from human serum.

　　仪器：TSQ Quantum Ultra mass spectrometer

　　结论：An h-mSRM- based assay for targeted proteins in human serum was developed on a TSQ Quantum Ultra triple quadrupole mass spectrometer. A total of 103 SRM transitions were monitored for the quantitation of 53 serum proteins. One exogenous protein, IL-6, was spiked to evaluate assay performance. Several unique features of the Quantum Ultra instrument contributed to the specificity, sensitivity, and robustness of this assay.

　　1) Q1 resolution of 0.2 FWHM dramatically reduced non-specific matrix interference from the serum background, dramatically improving assay specificity. At Q1 resolution of 0.4 or 0.7 FWHM, significant interference was seen in 25% of targeted transitions.

　　2) Analytical assay performance was excellent.

　　a) %CV varied from 5-26%, with 50% of protein CVs < 10%.

　　b) Peptide response was linear over four orders of magnitude.

　　c) Sensitivity was excellent, with the ability to detect proteins present at μg/mL levels and to detect IL-6 at levels as low as 20 amol on column.

　　d) SRM-triggered MS/MS spectra were of good quality and in most cases sufficient to permit confirmation of peptide ID by database searching with SEQUEST.