Methods for quantitative analysis by tandem mass spectrometry

DETAILED DESCRIPTION Embodiments of the present invention provide methods for deconvoluting contributions of a plurality of analytes utilizing a tandem mass spectrometry, or MS.
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n signal.
A tandem mass spectrometry signal including a plurality of peak intensities, generally at one or more mass transitions, is obtained wherein a plurality of analytes in a sample contribute to at least one of said peak intensities.
A model is provided relating one or more peak intensities to a contribution intensity for each of said analytes.
A contribution intensity for one or more analytes is then calculated using the model.
A calibration curve for at least one of the analytes is provided relating contribution intensity to concentration.
Based on the calibration curve, a concentration for at least one analyte is determined.
In some embodiments, the model used includes a system of linear equations.
In some embodiments, the mass spectrometry signal contains a number of peaks at least equal to the number of the target analytes of interest.
In other embodiments, there are a greater number of signal peaks than target analytes, and in other embodiments there are fewer signal peaks than target analytes, and at least one signal peak is monitored at a plurality of collision energies.
In some embodiments, the model includes representing the mass spectrometry signal as a weighted sum of reference signals, each reference signal corresponding to one of said analytes.
Embodiments of the present invention further include performing a quantitative calibration with authentic standards, internal standards, external standards, or a combination of standards may be utilized.
In embodiments of the present invention, the target analytes include isobars, and the quantitative concentration of one or more isobars in a sample can be determined.
In some embodiments, the target analytes include isomers.