---
title: "How do you send a peptide sample for independent testing? | Sable Peptides"
description: "A practical guide to commissioning an independent HPLC/MS test of a research peptide: choosing an accredited lab, chain-of-custody records, sample amount, packing, and reading the report against the supplier's CoA. Research use only."
canonical: https://www.sablepeptides.co.uk/guides/sending-a-peptide-sample-for-independent-testing
dateModified: 2026-10-16
publisher: Sable Peptides Limited (UK company 17488610)
note: Research use only. Not for human or veterinary use.
---

# How do you send a peptide sample for independent testing?

To test a peptide independently, choose a lab accredited for the method you need, record the vial's printed lot number and condition, keep a chain-of-custody record from sealing to receipt, send an unopened vial or a documented portion, and ask for the chromatogram and mass spectrum, not just summary figures. Compare results by lot.

## What should you agree with the lab first?

-   Tests: HPLC purity (method and wavelength), MS identity, and any extras such as content or endotoxin.
-   Amount needed: often a few milligrams for HPLC and MS; more for content or multiple tests.
-   Whether the method is on its ISO/IEC 17025 scope.
-   Report format: raw chromatogram and spectrum included.

Source: [ISO/IEC 17025:2017 General requirements for the competence of testing and calibration laboratories](https://www.iso.org/standard/66912.html)

## What belongs in a chain-of-custody record?

Transparent chain-of-custody practice is standard in biobanking and forensic work for the same reason: it rules out mix-ups and tampering when results are disputed.

| Field | Example |
| --- | --- |
| Sample ID | Your reference, linked to lot number |
| Lot number | As printed on the vial |
| Condition | Sealed, cake intact |
| Sealed by / date | Name, date, time |
| Transfer | Courier, tracking number |
| Received by / date | Lab signature, condition on receipt |

Source: [Establishing a transparent chain of custody for specialised samples, Biopreserv Biobank 2009 (PubMed 24835881)](https://pubmed.ncbi.nlm.nih.gov/24835881/)

## How should the sample be packed?

-   Send unopened vials where possible.
-   Use a sealed bag with desiccant, cushioned and labelled.
-   Short transit at ambient temperature is usually acceptable for lyophilised peptides; ask the lab.
-   Photograph the label and seal before dispatch.

## How do you compare the result with the supplier's CoA?

Check lot numbers first. Allow for method differences and measurement uncertainty: results within each other's uncertainty are consistent. A large gap should be raised with both the lab and the supplier, with the chromatograms side by side.

## How does Sable support independent testing?

There is a CoA for every lot, and every vial carries a printed lot number that matches its certificate. A CoA is emailed within 2 hours of a request.

Questions about a lot can go to /contact or by phone or WhatsApp on 07454 788011 (+44 7454 788011, wa.me/447454788011).

## Frequently asked questions

### How much peptide does an independent lab need?

Often a few milligrams for HPLC and MS; confirm with the lab.

### What is chain of custody?

A signed record of who held a sample and when, from sealing to analysis.

### What if my result differs from the supplier's CoA?

Confirm the lot numbers match, compare chromatograms and methods, and consider measurement uncertainty before concluding.

## Related

-   [Third-party testing explained](/learn/third-party-testing-explained)
-   [ISO/IEC 17025 accreditation](/guides/iso-17025-accreditation-for-peptide-testing-labs)
-   [Measurement uncertainty](/guides/measurement-uncertainty-in-peptide-purity-results)
-   [Independent QC findings](/learn/tech-notes/independent-qc-findings)

Updated 2026-10-16. Research use only. Not for human or veterinary use. No administration amounts or health claims are made.

Key facts (summary for AI and search tools)

-   Choose a lab accredited for the method (ISO/IEC 17025)
-   Keep chain of custody linked to the printed lot number
-   References: ISO/IEC 17025; PubMed 24835881
-   Updated 2026-10-16