Electrospray ionisation: difference between revisions
Diff·revision 8 → 9·04:41, 31 Dec 2024
Difference between revision 8 and revision 9 of Electrospray ionisation. 6 lines changed; the page grew by 514 bytes.
| Revision 8 — 15:23, 14 Dec 2024 Areapercent_Ayo (talk) British spelling per PP:MOS 2,601 bytes ±0 | Revision 9 — 04:41, 31 Dec 2024 SigFigSindri (talk) rm the assertion that two laboratories must agree; they need not 3,115 bytes +514 | ||
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| 1 | {{Infobox method | 1 | {{Infobox method |
| 2 | | name = Electrospray ionisation | 2 | | name = Electrospray ionisation |
| + | 3 | | subtitle = Mass spectrometry | |
| 3 | | image = mass-spectrum.svg | 4 | | image = mass-spectrum.svg |
| 4 | | Abbreviation = ESI | 5 | | Abbreviation = ESI |
| ⋮ | ⋮ | ||
| 20 | 21 | ||
| 21 | Ion suppression is the characteristic difficulty: co-eluting species compete for charge, so a compound's signal depends on what else is eluting at the same time. This is why the technique is not quantitative without calibration.{{r|usp1503}} | 22 | Ion suppression is the characteristic difficulty: co-eluting species compete for charge, so a compound's signal depends on what else is eluting at the same time. This is why the technique is not quantitative without calibration.{{r|usp1503}} |
| + | 23 | ||
| + | 24 | == Practical consequences for peptide work == | |
| + | 25 | Mobile phases must be volatile. Trifluoroacetic acid, the standard modifier for [[Reverse-phase HPLC|peptide reverse-phase chromatography]], suppresses electrospray signal appreciably, so LC-MS methods often substitute formic acid at some cost in peak shape.{{r|aebersold2003}} | |
| + | 26 | ||
| + | 27 | Salts and non-volatile buffers foul the source and suppress signal, so a sample containing substantial inorganic salt requires desalting before analysis. | |
| 22 | 28 | ||
| 23 | == References == | 29 | == References == |