Third-Party Tested Peptides: HPLC Purity, MS Identity and Lab Reports
Independent third-party laboratories, not Pepta Labs, run RP-HPLC purity and mass-spectrometry identity analysis on a sampled production run from the source. The lab report is sent by email on request, before you order if you want to see it first.
HPLC Purity Analysis
Independent High-Performance Liquid Chromatography reports provide the measured purity for listed compounds.
Certificate of Analysis
Sent by email on request, before you order if you want to see it first. Reports are not posted for download on product pages.
Analytical Documentation
Product records identify the CAS number, molecular formula, molecular weight, and sequence when applicable.
Third-Party Verified
Independent laboratories perform HPLC purity analysis and mass spectrometry identity confirmation on a sampled production run from the source. Pepta Labs does not test in-house.
How the third-party testing works
Pepta Labs is a supplier and reseller, not a manufacturer. Through a cooperative purchasing arrangement, multiple buyers combine volume orders placed directly with manufacturers and fund independent third-party analytical testing for the resulting production runs. Pepta Labs does not manufacture products, operate a production or ISO-certified facility, or perform in-house analytical testing. There is no in-house quality control step; the independent laboratory report is the only testing represented.
1
HPLC Analysis
Reverse-phase HPLC measures purity by separating the target compound from detectable synthesis byproducts and degradation artifacts. The result is reported as area-percent of the main peak and published on the product page.
2
Mass Spectrometry
Mass spectrometry compares the observed molecular mass with the expected mass for the stated compound as an identity check.
3
Identity Check
The report's compound name, formula and molecular weight can be checked against the listing's published chemical identity, including the sequence where applicable.
4
Matching a Report to an Order
Vial labels identify the compound, quantity and research-use designation. They do not carry lot or batch numbers. A report is matched to a purchase by compound name and order, not by a lot number.
What third-party tested means for a research peptide
For a research peptide, third-party tested means that the purity and identity analysis was run by an independent laboratory rather than by the seller, that the report states the method used, and that the report can be matched to the sample it describes, so the figure on the listing can be checked against a document. At Pepta Labs: Independent third-party HPLC purity analysis and mass-spectrometry identity confirmation, commissioned through the purchasing group on a sampled production run from the source. Pepta Labs does not test in-house.
Because testing is commissioned by the purchasing group, the client field may name the group or source rather than Pepta Labs, and supplier-identifying fields are redacted. Sent by email on request, before you order if you want to see it first.
| Item | Established by the sampled-run report? |
|---|
| RP-HPLC purity of the sampled production run | Yes. Reported as area-percent of the main peak; the figure is published on the product page. |
| Mass-spectrometry identity of the sampled production run | Yes. Reported as the observed mass against the mass calculated from the molecular formula. |
| Method, laboratory, date and sample identifier | On the report; available fields vary by report. |
| Which vial the report describes | No. A report is matched to the compound and quantity ordered, not to a vial; lot numbers are covered in step 4 above and in the FAQ. |
| Quantity in the vial | No. The listed quantity is a supplier-stated nominal quantity and is not independently verified by Pepta Labs (Terms 6.2). |
| Sterility, endotoxin or LAL, potency, pharmaceutical-grade, cGMP, contaminant-panel or vial fill-quantity testing | Not claimed (Terms 6.2). |
| Testing by Pepta Labs itself | None (Terms 6.2). See 'How the third-party testing works' above. |
| Certified reference material or pharmaceutical reference standard | Not claimed (Terms 6.4). |
If a protocol, institution or quality system requires a test that is not expressly stated, contact support@peptalabs.com before ordering (Terms 6.5). Full wording: Terms, section 6. Reading the report: how to verify a peptide COA.
What the lab report (Certificate of Analysis) contains
The lab report, a Certificate of Analysis (COA), records the independent laboratory's HPLC purity and mass spectrometry identity results for a sampled production run. Available fields vary by report, but the analytical information generally includes:
Cooperative Purchasing and COA Naming
Testing is commissioned and funded by the cooperative purchasing group. For that reason, the COA client field may name the purchasing group or source rather than Pepta Labs. Supplier-identifying fields are deliberately redacted before the report is shared.
| Field | Description |
|---|
| Product Name | The peptide name and catalog identifier |
| Molecular Formula | Chemical composition of the peptide |
| Molecular Weight | Expected mass in g/mol, confirmed by MS |
| HPLC Purity | Measured percentage purity from chromatography |
| MS Confirmation | Observed mass vs. expected — confirms identity |
| Appearance | White to off-white lyophilized powder |
| Storage Conditions | Recommended temperature for stability |
Request a peptide lab report by email
Tell us where to send it. The report shows the independent lab's HPLC purity and mass-spectrometry identity results for the production run we sourced. Ask before you order if you want to see it first.
Because testing is commissioned by the purchasing group, the client field may name the group or source rather than Pepta Labs, and supplier-identifying fields are redacted. Sterility, endotoxin or LAL, potency, pharmaceutical-grade, cGMP, contaminant-panel and vial fill-quantity testing are not claimed.
Or email support@peptalabs.com with the compound name.
Related reading: HPLC vs mass spectrometry · how to verify a peptide COA · peptide purity testing explained · browse the research peptide catalog.
Reported purity on listings
The reported RP-HPLC purity for each listed compound is published on its product page, as the independent laboratory's area-percent figure for the sampled production run. Across current listings the reported figures range from 98.0% to 99.5%. The lab report is sent by email on request.
| Item | What is reported |
|---|
| Purity method | Reversed-phase HPLC, area-percent of the main peak |
| Identity method | Mass spectrometry, observed mass against the expected mass |
| Reported purity, current listings | 98.0% to 99.5% RP-HPLC |
| Not claimed | Sterility, endotoxin or LAL, potency, pharmaceutical-grade, cGMP, contaminant-panel or vial fill-quantity testing |
Storage & Handling
Compounds ship as lyophilized powder at ambient temperature, without cold packs or insulated packaging. Lyophilized powder is substantially more thermally stable than the same compound in solution, and short-term ambient exposure in transit is not expected to meaningfully change measured purity.
On arrival, refrigerate sealed vials at 2–8°C or store at -20°C for long-term storage. Keep them protected from light and moisture.
Third-party testing and lab report FAQ
What purity are Pepta Labs peptides?
The reported RP-HPLC purity for each listed compound is published on its product page, as the independent laboratory's area-percent figure for the sampled production run. Across current listings the reported figures range from 98.0% to 99.5%. The lab report is sent by email on request.
Are Pepta Labs peptides third-party tested?
Independent third-party HPLC purity analysis and mass-spectrometry identity confirmation, commissioned through the purchasing group on a sampled production run from the source. Pepta Labs does not test in-house. Sterility, endotoxin or LAL, potency, pharmaceutical-grade, cGMP, contaminant-panel and vial fill-quantity testing are not claimed.
What is in a peptide lab report?
Two results: the RP-HPLC purity of the sampled production run, stated as area-percent of the main peak, and the mass-spectrometry identity, stated as the observed mass against the mass calculated from the molecular formula. Method conditions, the laboratory, the date and the sample identifier are on the report; available fields vary by report.
How do I get the lab report (Certificate of Analysis)?
The report is sent by email on request, before you order if you want to see it first. Use the request form on this page, or email support@peptalabs.com with the compound name and quantity. Reports are not posted for download. Because testing is commissioned by the purchasing group, the client field may name the group or source rather than Pepta Labs, and supplier-identifying fields are redacted.
Do the vials carry a lot number that matches the report?
Vial labels identify the compound, quantity and research-use designation. They do not carry lot or batch numbers. A report is matched to the compound and quantity ordered, not to a lot number printed on the vial; it is not a per-vial certificate.
How are research compounds shipped and stored?
Compounds ship as lyophilized powder at ambient temperature without cold packs or insulated packaging. Lyophilized powder is substantially more thermally stable than the same compound in solution, and short-term ambient exposure in transit is not expected to meaningfully change measured purity. Refrigerate at 2–8°C on arrival or store at -20°C long term.
Why might the COA client field not say Pepta Labs?
Pepta Labs is a supplier and reseller participating in a cooperative purchasing arrangement. The purchasing group commissions testing, so the COA client field may name the group or source rather than Pepta Labs. Supplier-identifying fields are redacted before sharing.
What does third-party tested mean for peptides?
For a research peptide, third-party tested means that the purity and identity analysis was run by an independent laboratory rather than by the seller, that the report states the method used, and that the report can be matched to the sample it describes, so the figure on the listing can be checked against a document. At Pepta Labs: Independent third-party HPLC purity analysis and mass-spectrometry identity confirmation, commissioned through the purchasing group on a sampled production run from the source. Pepta Labs does not test in-house.
What does a peptide COA not tell you?
Three things: which vial the report describes, the quantity in any vial, and anything not printed on the report. The report covers a sampled production run; it is matched to the compound and quantity ordered, not to a vial, and the listed quantity is a supplier-stated nominal quantity that Pepta Labs does not independently verify (Terms 6.2). Products are not certified reference materials or pharmaceutical reference standards (Terms 6.4).
Is every vial tested?
No. The report describes a sampled production run, not the vial you receive, so it is not a per-vial certificate. The listed quantity is a supplier-stated nominal quantity and is not independently verified by Pepta Labs.
Is sterility or endotoxin testing available?
No. Sterility, endotoxin or LAL and vial fill-quantity testing are not claimed on any listing (Terms 6.2). If a protocol, institution or quality system requires one of them, an unredacted report or another test not expressly stated, contact support@peptalabs.com before ordering and do not order unless the available documentation is adequate for the work (Terms 6.5). Products are not certified reference materials or pharmaceutical reference standards.