Methodological standard · §5
CEI-MS-10 — system suitability and acceptance criteria
The performance the system must demonstrate, and the criteria a result must meet to be reportable.
§5System suitability and acceptance criteria
§5.1System suitability
Table 1. System suitability criteria. A determination is reportable only where every criterion is met at the time of analysis.
| Parameter | Criterion | What it establishes |
|---|---|---|
| Calibration correlation coefficient | ≥ 0.995 | Curve linearity |
| Spike recovery in the peptide matrix | 90–110 % | Absence of matrix interference |
| Determined content versus theoretical maximum | Determined ≤ theoretical + 15 % | Consistency with the salt stoichiometry |
| Blank | Below the quantitation limit | Reagent purity |
§5.2Acceptance criteria
- Counter-ion identity must be stated. A content figure without an identity is not reportable.
- Content is reported as determined and compared against the theoretical maximum in the same table.
- For a net acidic peptide, an anion determination is recorded as not applicable and a cation determination is required.
§5.3Limitations
Compound Evidence Institute · CEI-MS-10/5 · https://compoundevidence.com/methods/counter-ion/acceptance-criteria/ · retrieved 30 July 2026