Peptides, explained plainly

What each research peptide is, where it stands legally, and how to judge its quality. Plain English, sourced, and honest about what isn't known.

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New to peptides? Read these in order.

1What a peptide isA peptide is a short chain of amino acids, the same building blocks as proteins, just fewer of...
2Research peptide vs. approved drugTwo vials can share a molecule's name and still be completely different products. Here's the difference, and why...
3How to read a study"Studies show" can mean a dish of cells, a few rats or ten thousand people. Here's how to...
4Where peptides stand legallyApproved, compoundable, research-only, banned in sport: what each status means, without the legal jargon.
5Quality, purity and COAsResearch peptides aren't made under drug-factory rules, so testing is your only window into the vial. Here's what...

Peptide library

What each one is, where it stands legally, and what a good COA shows.

Incretin & Amylin Analogues

TirzepatideA lab-made peptide designed to bind two gut-hormone receptors, GIP and GLP-1. It's the active ingredient in FDA-approved medicines; what...Read SemaglutideA lab-made peptide modeled on the gut hormone GLP-1. It's the active ingredient in FDA-approved medicines; what we sell is...Read

Tissue Research Peptides

TB-500A lab-made, seven-amino-acid fragment of thymosin beta-4 with an acetyl cap. It's a different molecule from full-length thymosin beta-4, and...Read GHK-CuA three-amino-acid peptide (glycine, histidine, lysine) bound to a copper ion. It isn't approved as a drug anywhere.Read BPC-157A lab-made 15-amino-acid peptide based on a protein found in human gastric juice. It isn't approved as a drug anywhere.Read

Quality & handling

How to read a COA, what purity means, and how peptides are stored.

The future of peptide research An overview of where peptide science is heading, from synthesis and analytical advances to new compound classes and the regulatory... Read How to store sealed peptide vials The four things that degrade lyophilized peptides, and the temperature, light and humidity conditions that keep sealed vials stable. Read Lyophilization: how freeze-drying preserves peptides How freeze-drying turns a peptide solution into a stable dry cake, the three phases of the process, and why dry... Read What are peptides? A beginner's guide The basics of peptide chemistry: what peptides are, how they differ from proteins, how they are made and why they... Read Peptide purity: what the number means What a 99% purity figure actually measures, what makes up the rest of the sample, and why net peptide content... Read How to read a certificate of analysis A section-by-section walkthrough of a peptide certificate of analysis: what each test shows, what a complete report looks like, and... Read

About Learn

Learn is written and owned by PeptideSupply. We cite our sources and say plainly when something isn't known. We don't give dosing or usage guidance: our products are sold for research use only, not for human or animal consumption, and nothing here is medical advice.