How to quantify an intact protein by multiple reaction monitoring?

05 May 2016 1 3K Report

According to some recent reports, several intact proteins,just like small-molecule compounds, can also be measured by LC-MS/MS with MRM mode. How to obtain and select the marker fragment(s) and then quantition of them with proper LC-MRM analysis?

Ujwal S. Patil

You can perform intact protein analysis with triple quad MS instruments, and multiple charged protein envelop spectra are normally acquired. It is difficult to do quantitation with protein data, usually a software to deconvolute the intact protein spectra is used. I decided not to go that way since we found alternative HPLC-UV method for our proteins.

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