A peptide Certificate of Analysis is a batch-specific lab report. The two fields that decide whether a lot is usable in a protocol are HPLC purity (how much of the sample is the target peak) and mass-spectrometry identity (whether that peak has the expected mass). If either is missing, the COA is incomplete.

Research use only. This page is a documentation guide for laboratory staff. Helivex compounds are not approved for human or veterinary use.

What a COA must identify

Before you look at the chromatogram, confirm the document is about the vial you received:

• Compound name and, when assigned, CAS number
• Lot or batch number that matches the label
• Stated amount and salt form (for example acetate)
• Test date and the laboratory that issued the report
• A verification path (QR code, report ID, or public lookup on the lab site)

A PDF with a purity number and no batch ID, no chromatogram, and no issuing lab is not a verifiable COA. That is the most common complaint researchers raise when they compare suppliers.

HPLC purity: what the number actually means

HPLC (high-performance liquid chromatography) separates components in the sample. The main peak area divided by total peak area is reported as percent purity. A single dominant peak with small satellite peaks is the expected pattern for a well-purified lyophilized peptide.

Treat the chromatogram as part of the result, not decoration. A 99% figure without a trace cannot be checked for integration errors, solvent peaks, or a second large impurity hiding under the main peak.

Many research groups use ≥98% or ≥99% HPLC as an acceptance criterion. Helivex lists lots against a 99%+ HPLC target and publishes the supporting report on the COA page.

Mass spectrometry: identity, not purity

MS (often LC-MS or ESI-MS) answers a different question: does the main species have the molecular mass expected for that sequence and salt form? A correct mass supports identity. It does not replace HPLC for purity. MS-only or UV-only reports leave a gap.

See HPLC vs mass spectrometry for when to require both.

How to verify the report is genuine

1. Open the issuing laboratory’s own site (not a screenshot on a sales page).
2. Enter the report ID, unique key, or scan the QR code.
3. Confirm compound name, batch, and purity match the PDF on the supplier site.
4. Reject reports with the client, manufacturer, or unique key blanked out if you cannot complete that lookup.

Red flags

• “COA available on request” with no public batch file
• One recycled PDF used across many lots
• Purity stated without method (HPLC vs UV vs “tested”)
• No chromatogram, no mass, no lab name
• Dates far older than the lot on the vial

FAQ

Is a supplier in-house QC sheet the same as a COA?

No. In-house QC can be useful process control. A COA that other labs can independently look up is a stronger identity and purity record.

Does a high HPLC number guarantee the sequence is correct?

No. HPLC says the sample is mostly one species. Mass spec (and, when needed, additional orthogonal methods) supports that the species is the intended peptide.

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