Methods explainer
Purity testing methods: HPLC and mass spectrometry
A research-peptide certificate of analysis reports identity (usually by mass spectrometry) and purity (usually by high-performance liquid chromatography). This page is a generic explainer of each method — not a report of any specific numeric value from the Wolverine Blend supplier record. See the batch documentation page for live lot values when available.
Last updated .
HPLC — reported purity
High-performance liquid chromatography (HPLC) pushes a dissolved sample through a packed column at high pressure. Each component travels at a different speed depending on how strongly it interacts with the column and the solvent. A detector at the end of the column records a signal over time, producing a chromatogram whose peaks correspond to the components in the sample.
| Headline figure | A single percentage number, e.g. 99.XX% This is the integrated area of the target-peptide peak divided by the sum of all peak areas (at the detection wavelength). |
|---|---|
| Detection | Usually UV absorbance at a fixed wavelength (often 214 nm or 220 nm for peptide bonds). |
| Chromatogram | A time-vs-signal plot; the main peak is the target peptide, with smaller peaks indicating related impurities. |
| What it does not tell you | Identity — HPLC alone cannot confirm the material is the stated peptide; that is what mass spectrometry is for. |
Mass spectrometry — identity
Mass spectrometry measures the mass-to-charge ratio of ions produced from a sample. For a peptide, this means the observed mass of the molecular ion is compared with the mass predicted from the stated amino-acid sequence. A match within a few daltons (or a few parts per million on high-resolution instruments) supports the identity claim.
| Headline figure | Observed mass of the molecular ion vs. the expected mass of the sequence. |
|---|---|
| Common ionisation | Electrospray ionisation (ESI) or matrix-assisted laser desorption/ionisation (MALDI). |
| What it confirms | That the mass of the main component matches the stated sequence (identity). |
| What it does not tell you | How pure the sample is — that is what the HPLC chromatogram is for. |
What to check on a COA
- Lot or batch accession. A unique string tying the tests to a specific manufacturing run.
- Test date. When identity and purity were tested; not an expiration date.
- Reported purity. A single percentage from HPLC at a specified detection wavelength.
- Reported identity. An observed mass compared with the expected mass of the stated sequence.
- Chromatogram image. Confirms the peak integration matches the reported purity.
What this site publishes
This page is a generic explainer of the methods. It does not quote a purity number for Wolverine Blend. The current lot's accession, test date and reported purity — if reachable — are shown on the batch documentation page and on the home-page documentation card. If a value cannot be verified from the live supplier record it is left blank, never invented.