Quality and documentation
How to judge a research peptide before you buy.
A purity figure on a product page is a claim. A document is evidence. Here is what a document should show, what the methods behind it can and cannot tell you, and what to ask any supplier, including us.
- Documents listed by batch
- Methods explained plainly
- Research use only
- The name and amount on the document match the label
- The batch on the document is the batch you are asking about
- It says who carried out the analysis, and when
- Identity and purity are reported as two separate results
What a document should show
Four things to look for.
Identity
Usually confirmed by mass spectrometry, which checks the measured molecular mass against the expected one.
Purity
Usually measured by HPLC, which separates the components of a sample and reports the target as a share of everything detected.
Batch and date
A document belongs to one batch. It should name that batch, who carried out the analysis and when.
What a figure leaves out
A purity percentage is a ratio of peak areas under one set of conditions. It does not describe the mass in a vial, sterility or storage since the test.
Before you order anywhere
Five questions worth asking any supplier.
They take a minute to ask and a good supplier can answer every one. They apply to us as much as to anyone.
Is there a document for this batch?
A certificate describes the batch it was run on. One from an earlier batch says nothing about the vial being sold today.
Who ran the analysis, and when?
A document should name the laboratory and the test date. Without them there is nothing to check it against.
Which methods were used?
Identity and purity are different questions, usually answered by mass spectrometry and by HPLC. A document should say which method gave which result.
Does it match the label?
The product name and the amount on the document should be the ones printed on the container.
What happens when there is no document?
The honest answer is “then we do not claim a result”. Be wary of a figure that has no document behind it.
How Horizon Peptides answers them
Batch documents are published on our Lab Results page as they become available, searchable by product name or batch. Not every batch has a published document. Where one exists it is listed; where it does not, the page says nothing about that batch rather than implying a result.
If you need a document for a particular product or batch and cannot find it, ask through the contact page and we will tell you what is available.
Where to read more
The documents, and how to read them.
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Our approach
Quality & Testing
How documentation is handled, and how to read a certificate of analysis when one is published.
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Documents
Lab Results
Batch documents as they become available, searchable by product name or batch.
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Guide · 4 min
How to Verify a Peptide
Reading an HPLC trace and a mass spectrum.
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Guide · 12 min
Analytical Methods for Peptides
What HPLC, mass spectrometry, amino acid analysis, water, counter-ion, endotoxin and sterility tests each answer, and what they cannot.
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Guide · 12 min
Certificate of Analysis Guide
Every field on a certificate of analysis, how to tell a batch document from a generic one, and what a certificate cannot prove.
Documentation
Documents, not adjectives.
See what we publish, what we do not, and how to read a certificate of analysis when one exists.
For research use only
Every product on this site is supplied for laboratory research use only. Products are not for human or veterinary consumption and are not intended to diagnose, treat, cure or prevent any condition. We do not provide dosing or administration guidance. Read our research use policy.