Mass spectrometry (revision 1)
Old revision·02:39, 30 Jun 2024·ImportRecordIna
This is an old revision of this page, as it stood at 02:39, 30 Jun 2024, saved by ImportRecordIna with the summary start article on the analytical method. It may differ substantially from the current revision, and any error it contains may since have been corrected.
| Mass spectrometry | |
|---|---|
| Measures | Mass-to-charge ratio of ions |
| Usual ionisation for peptides | Electrospray |
| Answers | What the molecule is; not how much unless calibrated |
| Analytical method infobox · conventions | |
Mass spectrometry measures the mass-to-charge ratio of ionised molecules. For peptides it is the ordinary means of confirming identity: an observed molecular mass agreeing with the calculated mass excludes most alternatives, and fragmentation can confirm the sequence itself.[1]
A purity determination by chromatography establishes that one species dominates a sample; it does not establish which species. These are separate questions and require separate determinations. A certificate reporting purity but no identity leaves the more fundamental of the two unanswered.[2]
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