Method for linear quantitative dynamic range extension

A method of mass spectrometry, comprising:

• mass analyzing n known types of ions of a compound of interest over time in each of m different experimental samples, producing n extracted ion chromatogram (XIC) peaks for each of the m different samples, each type of ion having a numerical label i;
• selecting a reference ion j that is a j ion of the n types of ions or a hypothetical ion j;
• calculating a ratio r(j,i) of a peak area of the j ion to a peak area of each ion of the n types of ions for each of the m samples, producing m r(j,i) ratios for each of the n types of ions;
• calculating an expected ratio rq (j,i) for each ion of the n types of ions from the m r(j,i) ratios for each of the n types of ions;
• and
• for each sample of the m samples, calculating an uncertainty weighted average quantity, X, from
• X
• =
• 1
• Σ
• i
• =
• 1
• :
• n
• ⁢
• w
• i
• ⁢
• ∑
• i
• =
• 1
• :
• n
• w
• i
• ×
• r
• q
• (
• j
• ,
• i
• )
• ×
• A
• i
• ,
• where wi is an uncertainty weight between 0 and 1 for each ion of the n types of ions for the each sample with a value closer to 1 meaning less uncertainty and a value closer to 0 meaning more uncertainty, and where Ai is a peak area for each of the n types of ions.

A computer program product, comprising a non-transitory tangible computer-readable storage medium whose contents include a program with instructions being executed on a processor for a mass spectrometry method, comprising:

• providing a system, wherein the system comprises one or more distinct software modules, and wherein the distinct software modules comprise a control module and an analysis module;
• instructing a mass spectrometer to mass analyze n known types of ions of a compound of interest over time in each of m different experimental samples using the control module, producing n extracted ion chromatogram (XIC) peaks for each of the m different samples, each type of ion having a numerical label i;
• selecting a reference ion j that is a j ion of the n types of ions or a hypothetical ion j using the analysis module;
• calculating a ratio r(j,i) of a peak area of the j ion to a peak area of each ion of the n types of ions for each of the m samples using the analysis module, producing m r(j,i) ratios for each of the n types of ions;
• calculating an expected ratio rq (j,i) for each ion of the n types of ions from the m r(j,i) ratios for each of the n types of ions using the analysis module;
• and
• for each sample of the m samples, calculating an uncertainty weighted average quantity, X, from
• X
• =
• 1
• Σ
• i
• =
• 1
• :
• n
• ⁢
• w
• i
• ⁢
• ∑
• i
• =
• 1
• :
• n
• w
• i
• ×
• r
• q
• (
• j
• ,
• i
• )
• ×
• A
• i
• using the analysis module, where wi is an uncertainty weight between 0 and 1 for each ion of the n types of ions for the each sample with a value closer to 1 meaning less uncertainty and a value closer to 0 meaning more uncertainty, and where Ai is a peak area for each of the n types of ions.