Our Testing Standards
Improved Peptides has its research peptides independently tested by a third-party laboratory before release. Material is analysed for purity by high-performance liquid chromatography (HPLC) and for identity by mass spectrometry, and is documented with a batch-specific Certificate of Analysis (COA). Batch-specific COAs are linked where available, including in our COA Library. This page explains what is tested and why. All products are supplied for laboratory research use only.
Independent third-party testing
Testing is performed by an independent third-party laboratory — not in-house. The distinction matters: a supplier’s own internal claim of quality is not verifiable, while an independent laboratory result is. Independent testing is the standard a research buyer should expect, and the laboratory that performed each analysis is the laboratory named on each COA.
HPLC purity analysis
High-performance liquid chromatography separates the components of a sample so the proportion that is the intended peptide can be measured. The HPLC result is the batch’s purity figure — how much of the material is the intended compound versus other components. Purity is reported per batch on the COA.
Mass-spectrometry identity confirmation
Mass spectrometry measures the molecular weight of the compound in the sample and confirms it matches the expected molecular weight of the intended peptide. This verifies identity — that the material is the compound it is labelled as. Purity and identity are different questions, which is why both tests are run: a sample can be highly pure and still be the wrong compound, or be the right compound with low purity.
Batch-specific Certificates of Analysis
Each batch carries a unique lot number, and that lot number is tied to its Certificate of Analysis. This batch-level traceability means a result is linked to the specific material it was measured on, rather than to the product in general. Batch-specific COAs are linked where available in our COA Library, organised by product — including widely studied research compounds such as BPC-157 and TB-500. For a walkthrough of how to interpret a COA, see how to read a peptide COA.
Handling and shipping
Peptides are supplied lyophilized (freeze-dried). Material is handled and shipped in line with standard practice for lyophilized research peptides, including temperature-controlled handling where appropriate.
Further reading
For educational, research-framed guides on evaluating suppliers — including how to evaluate research peptide vendors — and testing documentation, see the Research Library. To browse available research peptides, visit the shop.
Frequently asked questions
Are Improved Peptides products third-party tested?
Yes. Research peptides are independently tested by a third-party laboratory for HPLC purity and mass-spectrometry identity, and are documented with a batch-specific Certificate of Analysis. Batch-specific COAs are linked where available, including in the COA Library.
What is the difference between HPLC and mass spectrometry?
HPLC measures purity — how much of the sample is the intended peptide. Mass spectrometry confirms identity — that the compound matches the expected molecular weight. Both are used because purity and identity are different questions.
Why does independent testing matter?
A supplier’s own internal claim of quality cannot be verified by a buyer. An independent third-party laboratory result can be. Independent testing provides documentation that does not depend on the supplier’s word alone.
Where can I see the COA for a product?
Batch-specific COAs are linked where available in the COA Library. If a COA for a specific batch is not yet posted, contact us with the batch or lot number for the relevant document.
What does a COA actually confirm?
A Certificate of Analysis confirms the identity and purity of a research compound for a specific batch. It does not indicate any health, safety, or efficacy outcome — these are research compounds for laboratory use only.
Research Use Only. This page is an educational summary and is not medical advice. Improved Peptides products are sold strictly as research chemicals for in-vitro laboratory research. They are not drugs, supplements, or foods, and are not intended for human or animal consumption, diagnosis, treatment, or to prevent any condition.