Guides
Peptide comparisons
Peptides come in pairs that get confused: a native form and a modified one, two agonists at one receptor, a full peptide and its active fragment. Each page here sets out what is actually different, molecule by molecule.
Compare the molecule
Sequence length, molecular weight, the receptor it was built for, and whatever modification changes its stability. Those four facts separate almost every pair. Claims about what a peptide does belong to the research literature, and these pages point there rather than repeat it.
The report settles it
Two peptides with different sequences have different masses, and the mass-spec line on a report reads that mass. If you are unsure which of two similar peptides is in a vial, the expected mass on its report is the answer. On a pepuro vial, that report is one scan away.
Common questions
What does N-acetyl amidate mean on a peptide?+
An acetyl group on one end and an amide on the other. Both caps protect the sequence from the enzymes that trim peptides from their ends. The sequence between them is unchanged, and the molecular weight is slightly higher.
Are CJC-1295 DAC and no-DAC the same?+
No. Both are modified GHRH(1-29), but the DAC version carries a drug affinity complex that binds albumin and extends its half-life from minutes to days in research models. They differ by about 280 g/mol.
Is a fragment the same as the full peptide?+
No. A fragment is a short piece of the full sequence, chosen because it carries one specific activity. TB-500 fragment 17-23 is seven residues of a 43-residue peptide.
Both sides of every comparison are in the catalog.
Browse every peptideGuides
- Cagrilintide vs Semaglutide: amylin analog vs GLP-1 analogThey are paired in research, not interchanged. Cagrilintide acts at amylin and calcitonin receptors; semaglutide at the GLP-1 receptor. Different hormones, different masses.
- CJC-1295 DAC vs no-DACSame GHRH backbone, one extra chemical group. What the drug affinity complex does to half-life and mass, and how to tell the two apart on a report.
- GHK-Cu vs GHK basicThe same three amino acids, with and without the copper ion. What the copper adds to the mass, the colour and the chemistry.
- GHRP-2 vs GHRP-6 vs ipamorelinThree ghrelin receptor agonists that differ by one design goal: selectivity. Sequences, masses, and what separates a selective agonist from a broad one.
- Melanotan 1 vs melanotan 2 vs PT-141Three melanocortin peptides: one linear, one cyclic, and one derived from the cyclic form. Sequences, masses and receptor targets.
- Peptide blends vs single vialsA blend fixes the ratio and saves a vial. Single vials let you set the ratio and check each component's report. When each one makes sense.
- Semaglutide vs Retatrutide: one receptor or threeSemaglutide is a 31-residue GLP-1 analog. Retatrutide is a 39-residue triple agonist. 618 daltons and two receptors separate them.
- Semaglutide vs tirzepatide vs retatrutideThree incretin peptides, one, two and three receptors. How they differ by sequence, size and receptor target, and what tells them apart on a lab report.
- Semaglutide vs Tirzepatide: what is the difference?One receptor or two, 31 residues or 39, and a 700 dalton gap on the mass spec. How the two most-ordered GLP-1 research peptides differ, molecule by molecule.
- Semax vs selankTwo Russian heptapeptides from completely different parents. Sequences, masses, and why the acetylated amidated versions weigh more.
- Sermorelin vs CJC-1295 (no DAC): four substitutions apartBoth are GHRH(1-29). CJC-1295 no DAC edits four residues for stability and gains ten daltons. Why they are easy to confuse and how a report keeps them straight.
- Sermorelin vs tesamorelin vs CJC-1295Three GHRH analogs built on the same fragment, each stabilised a different way. Masses, modifications and what tells them apart.
- TB-500 vs TB-500 fragment 17-23A 43-residue peptide and the seven residues inside it that do the actin binding. Masses, and why the fragment weighs a seventh as much.
- Tirzepatide vs Retatrutide: dual agonist or triple?Both are 39 residues with a C20 fatty chain. Retatrutide adds the glucagon receptor and drops 82 daltons. What separates them on paper and on a lab report.
- BPC-157 vs TB-500: what's the difference?BPC-157 and TB-500 are two distinct research peptides studied in tissue-repair models. Here's how they differ by sequence, size, and research context - and how to verify either.