Xcel Peptides: research materials for qualified researchers
A U.S.-based supplier to qualified researchers and licensed laboratories. Independent third-party labs test what we list, and registered researchers can see the test documentation. Registration is free.
Independent third-party testing
We use independent third-party laboratories to test the materials we supply.
A U.S. company you can reach
Support answers account, order and shipping questions by email.
Free registration
Registration is free for qualified researchers and laboratories.
What a free researcher account gives you
01
The research catalog
Registered researchers can browse the full catalog and place orders. The catalog is not shown to the public.
02
Test documentation
Independent third-party test documentation is available for the materials you order.
03
Research-purpose checkout
At checkout you confirm your research purpose and that the material is for laboratory use only. It takes a minute and keeps every order on the record.
How we think about testing
A purity figure is only useful when you know what was measured, by whom, and what the method cannot see. Our Research News section explains the methods in plain language: chromatography, mass spectrometry, elemental analysis and how to read a certificate of analysis.
A complete test file answers five questions
1. Which method was used, and on what instrument?
2. Which batch does the file cover, and on what date was it tested?
3. Was identity addressed by a named method?
4. Where a purity method applies, was purity reported by a named method?
5. Was content measured separately from purity?
Research material categories
Free researcher account required. Sign in or register to view the catalog.
From Research News
A plain guide to what elemental analysis, liquid chromatography and LC-MS each measure for a peptide sample, and what each one cannot tell you.
A plain-language guide to what a UHPLC purity percentage tells you about a peptide sample, what it cannot see, and what to ask next.
Two labs can report different area-percent purity for the same material. Learn how column, gradient, wavelength and integration change the number.
Testing glossary
Plain-language definitions of identity, purity, content, counterion, co-elution, mass balance and certificate of analysis.
Who we sell to
We sell only to qualified researchers and licensed laboratories: independent researchers, research institutions, analytical laboratories and similar buyers. Materials are for laboratory research only. We do not sell to the general public.
Still need help?
Support can help with account access, order status and shipping, including if you cannot sign in.
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