Mass spectrometry (MS) confirms that a sample contains the expected peptide by measuring its molecular weight. It is a critical identity test that complements HPLC purity analysis.
How It Works
Peptides are ionized and passed through a mass analyzer. The mass-to-charge ratio (m/z) of ions is measured, producing a spectrum. The observed mass is compared to the theoretical mass calculated from the amino acid sequence.
Interpreting MS Results
- Exact match: Observed mass matches theoretical mass within acceptable tolerance (typically a few Daltons).
- Mismatch: May indicate wrong peptide, degradation, or modification.
Why MS Matters
HPLC confirms purity (how much of the target is present) but cannot definitively identify the compound. MS confirms identity (that the target is correct). Both tests together provide full quality assurance.
Our COAs include mass spectrometry verification for every batch, performed by independent laboratories.