Peptide Education
Plain-English explainers on the ideas every peptide shares: what a peptide is, how one is written down, how a lab checks what is in a vial, and how to read the paperwork that comes with it.
Each article is written by a named scientist, who checks its claims against the sources listed under it and approves the text before it is published. For one compound in depth, see the Research Hub and the Reference Library.
Latest articles
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Reading order
Each idea builds on the one before it: the molecule first, then how it is made and labeled, then how a lab tests it and reports the result. New articles join the list as their authors finish them.
The building blocks
What a peptide is, the bond that holds it together, and how its sequence is written down.
- 1What Is a Peptide? Amino Acids, Peptides and Proteins ExplainedAmino acids, peptides and proteins aren't three kinds of molecule. They're the same building blocks at different lengths, and the line between them is a convention.Dr. Sufia Ul Haque · 5 min read
- 2What Is a Peptide Bond?A peptide bond joins one amino acid to the next. It has partial double-bond character, which makes it flatter and less flexible than it first appears.Dr. Sufia Ul Haque · 6 min read
- 3How to Read a Peptide SequenceA peptide sequence is a sentence read in one direction. The small marks at either end, such as Ac- and -NH2, aren't decoration: they change the molecule and its weight.Dr. Sufia Ul Haque · 5 min read
How a peptide is made
How a chain is built one amino acid at a time.
- 4How Peptides Are Made: Solid-Phase Synthesis ExplainedIn preparation
The numbers on a label
Molecular weight, salt forms and registry numbers.
- 5What Is Molecular Weight? And Why the Salt Form Changes ItThe same peptide can carry two molecular weights on two documents, and both can be right. One describes the peptide alone; the other, the salt it's supplied as.Dr. Sufia Ul Haque · 5 min read
- 6What Is a CAS Number, and Why Can One Peptide Have Two?In preparation
How a lab checks a vial
How purity is measured, what the trace shows, what the number means, and how identity is confirmed.
- 7HPLC Explained: How Labs Measure Peptide PurityIn preparation
- 8How to Read a ChromatogramIn preparation
- 9What Does ">99% Purity" Actually Mean?">99% purity" describes the signal on an HPLC trace, not the weight of the powder. A vial can be more than 99% pure and still be partly water and salt.Julia Piccoli, PhD · 6 min read
- 10Mass Spectrometry: How Labs Confirm a Peptide's IdentityIn preparation
The document that reports it
Reading a certificate of analysis from top to bottom.
