Is it possible give me your idea about how we can determine exact mass of one protein that is modified? Recently I have got digest mass for my product that is shown 1 H extra could you tell me how is possible? Are there any opportunity in INTACT or digestion method determined just positive ion part of a salt in protein?
Do I understand this correctly: you gave your protein away for a mass spectrometric analysis, now you got the results back and it has a proton too much?
Please check whether the mass has been measured in the anion channel, some MS analysis software packages add a proton automatically in that case since they "assume" that the anion has been generated by deprotonation. If your anion is still completely protonated, these algorithms may lead to errors. Please consult your MS operator whether their software is one of these.
Thank you so much for your explanation, Our result was detected in M+2H in this case our product increased 33 but we had expected to get 32. Now I would like to know how is possible if my product with 33 increased a mount of the mass find a positive charge?
So your product is detected as a doubly charged cation?
Is the modification you are searching for with 32 mass carrying an intrinsic negative charge? This would explain the extra proton, as you would need 3 protons to observe a doubly charged species in that case.
- Badges
- Science topic
- Similar topics
- Chemistry
- Sulfites
- Inorganic Chemistry
- Inorganic Chemicals
- Salts