Dear Researchers,

I'm trying to develop the quantification of endogenous peptide in tissue using IDMS as the primary method of characterization. I performed analysis for the calibration curve of stable isotope dilution using tissue matrix. So I have peak area of dilution isotope labeled peptide and endogenous peptide

Then I plan to add isotope-labeled peptides so that the ratio of native peptides to isotopes is 1:1, and use the calibration curve above to calculate the endogenous (or native) peptides.

Then, how do I calculate the concentration of the endogenous peptide in the samples using IDMS method? Is there any step-by-step protocol/SOP/documents that I can refer to?

Thanks in advance.