One COA per lot
Each lot has its own certificate and lot number. One PDF reused across lots is a reference document, not the COA for your order.
SeqLine Bio · Supplier with COA
Buyer guide · COA-backed supply
What to expect from a peptide supplier with COAs
Many suppliers say they provide a COA. This page lists what that should mean in practice, so you can compare suppliers on the same terms.
Six things to expect
What “with COA” should include.
Complete fields
Product, strength, lot number, dates, specification, result, method and approval. See how to read a COA.
Purity and identity
HPLC purity against a stated specification, and MS molecular weight for identity. Purity alone doesn’t confirm what the compound is.
Access before payment
The COA for the lot you would receive, sent with the quotation or published online. See current-batch COA.
Clarity on who tested
Whether the COA comes from in-house QC or an outside lab, and whether the chromatogram and spectrum are available on request.
Terms for when it’s wrong
Written terms for a lot that fails your own test: retest, replacement or refund. See independent testing.
At SeqLine Bio
Every published lot has a public COA.
No login, no request needed. The quotation also includes the COA for the lot you would receive.
- HPLC purity against our release specification, NLT 98.0%
- MS molecular-weight identity
- Lot number, manufacturing, test and retest dates
- A QR code linking to the online record
Public records reproduce the source COA held in our quality records. A confirmed quality issue is replaced or refunded under the quality policy.
FAQ
Questions buyers ask.
Does SeqLine Bio provide COA, HPLC and MS documents?
Yes. Every published lot has a public COA in the COA library showing HPLC purity and MS molecular-weight identity. A separate chromatogram or spectrum is provided where that file exists; ask for it with your RFQ.
Why must the COA match the lot?
A COA describes one lot. A report from another lot shows the supplier’s past results, not the material you receive.
Can a buyer request independent testing?
Yes. Test a sample order of 1 kit (10 vials) in your own lab or, for qualified bulk RFQs, have a sealed sample of the intended lot sent to a lab you name.
Next step
Send your compound list and document requirements.
We reply within 4 business hours with price, lead time and the COA for the lot you would receive.