COA: batch summary
A Certificate of Analysis summarizes specification and result fields for a referenced lot.
Pepti · Buyer verification guide
Factory-direct peptide supplier · buyer verification
Peptide COA, HPLC and MS explained
Understand the difference between a peptide Certificate of Analysis, an HPLC purity result and an MS molecular-weight identity result, including what each can and cannot establish.
Direct answer
Verify the product, the documents and the lot.
COA, HPLC and MS answer different procurement questions. A COA summarizes a referenced lot, HPLC data supports chromatographic purity review, and MS data supports molecular identity review. A purity percentage alone does not prove identity, fill quantity, sterility or suitability for a particular use.
HPLC: chromatographic purity
HPLC separates detected components and reports chromatographic information such as peak area. Method context matters.
MS: identity support
MS provides observed mass information used to support compound identity.
SDS/MSDS: safety information
An SDS addresses handling, storage and transport safety. It is not a purity report.
Third-party report: independent layer
Independence is strongest when the buyer controls sample selection or uses a laboratory it trusts.
Pepti verification path
Documentation first, independent testing when required.
Pepti publishes batch-linked COA summaries in the public library for listed products and specifications. Each public record reproduces the HPLC purity and MS molecular-weight identity results reported within the source batch COA. It does not claim that separate chromatogram or spectrum files exist unless those files are actually available.
Batch documentation
The public COA summary, reported analytical results and Pepti lot reference are connected to one canonical batch record.
Small trial order
Receive the product first and independently test a buyer-selected sample before scaling.
Qualified bulk verification
For larger procurement, align the analytical panel and sample selection before scaling.
FAQ
Questions B2B peptide buyers ask.
Are COA, HPLC and MS the same document?
No. A COA summarizes batch results. HPLC supports chromatographic purity review, while MS supports molecular-weight identity review. Results may be reported inside a COA even when separate plot files are not published.
What is the most important field?
There is no single magic field. Buyers should review compound identity, lot reference, date, specification, HPLC purity, MS identity and the document conclusion together.
Does 99% HPLC purity prove peptide identity?
No. A purity percentage alone does not establish molecular identity; an MS molecular-weight result addresses a separate analytical question.
Is every Pepti public COA an independent third-party laboratory report?
No. A Pepti public page or presentation copy is a batch-linked summary reproduced from the source COA held in Pepti quality records. It is not described as an independently issued third-party laboratory certificate. Independent local verification is welcome, independent third-party testing is available, and confirmed quality issues are eligible for replacement or refund under the quality policy.
Does the public COA include a standalone chromatogram or mass spectrum?
Not necessarily. The public page reports only the analytical facts verified in the source batch COA. A separate chromatogram or spectrum is described only when that separate file actually exists.
Verify before scaling
Send the compound, quantity and document requirements.
Pepti replies with factory-direct pricing, public COA availability where listed, lead time and a practical verification path.