CJC-1295 With DAC or Without DAC: What the Difference Actually Is

Search for CJC-1295 in Canada and you land in an argument about four letters. Some listings say with DAC, some say without DAC, some say Mod GRF 1-29, and a fair number say nothing at all. They are not interchangeable, and the difference is not marketing — it is a covalent modification that changes the molecule, its mass, and what a certificate of analysis for it should look like.

What DAC actually is

DAC stands for Drug Affinity Complex. It is a maleimide group attached to the peptide, and its purpose is chemical rather than biological: the maleimide forms a covalent bond with cysteine-34 of serum albumin. Bound to albumin, the peptide is cleared far more slowly than it would be on its own. That is the whole of the modification. It does not change the receptor the peptide was designed around; it changes how long the molecule persists.

Because DAC is an added chemical group, a DAC-modified peptide has a different molecular formula and a different mass from the unmodified sequence. Any certificate that reports a mass consistent with the unmodified peptide is, by definition, not describing a DAC-modified one.

What we supply, and what it is called

ExoLabz supplies the unmodified version. On our label and certificate it reads CJC-1295 without DAC, and the identity block on that page states the alternative name it is known by in the literature:

• Compound: CJC-1295 without DAC (Mod GRF 1-29)
• Sequence: [D-Ala2, Gln8, Ala15, Leu27]-GRF(1-29) amide
• Molecular formula: C152H252N44O42
• Molecular mass: 3367.9 g/mol
• CAS registry number: 863288-34-0

So “CJC-1295 no DAC”, “CJC-1295 without DAC” and “Mod GRF 1-29” all describe the same material. If you searched for one and found the other, you are in the right place. If you are specifically looking for the DAC-modified version, we do not stock it, and we would rather tell you that than sell you the other one and let you discover it from the mass on the certificate.

Reading the sequence notation

The bracketed prefix is not decoration. [D-Ala2, Gln8, Ala15, Leu27] lists four substitutions against the natural GRF(1-29) sequence, at positions 2, 8, 15 and 27. The D-alanine at position 2 is the one that matters most analytically: position 2 is where dipeptidyl peptidase-4 cleaves the native sequence, and a D-amino acid there is not a substrate for it. The terminal amide tells you the C-terminus is capped as an amide rather than left as a free acid, which is a one-dalton difference that shows up in mass spectrometry.

If you are comparing two suppliers, compare the sequence strings character by character, not the product names. Names are marketing. Sequences are not.

Why it is so often sold paired with Ipamorelin

The CJC-1295 and Ipamorelin blend puts both compounds in one vial. They are different classes of molecule: the CJC sequence is a 29-residue GRF analog at 3367.9 g/mol, while Ipamorelin is a pentapeptide at 711.9 g/mol with the sequence Aib-His-D-2-Nal-D-Phe-Lys-NH2 and CAS 170851-70-4. Roughly a five-fold difference in mass, and completely different chemistry.

That size difference has an analytical consequence worth knowing: on a single RP-HPLC run the two elute at different retention times, so a certificate for a blend should show two resolved peaks, not one. If a blend certificate shows a single peak and a single purity figure, ask what it is a figure for.

What a certificate can and cannot settle

Mass spectrometry answers what the compound is by comparing observed mass against the calculated mass for the intended sequence — including the amide cap and every substitution. RP-HPLC answers how uniform it is. Neither says anything about sterility, endotoxin or residual solvents, and a report that does not list those tests did not run them.

Where a lot has been tested, its certificate is published on the product page or gathered on the certificates of analysis page, and your vial is matched to it by cap and crimp colour rather than a printed lot code. Not every lot has one posted; when yours does not, ask and we will send what we hold for it. If an independent laboratory disagrees with a certificate, the purity guarantee refunds the product and the test.

Ordering in Canada

Both the single-compound vial and the blend ship from inside Canada, which means no customs step and no importer-of-record question. Cost per milligram for every vial size is listed on the price index, quantity pricing is applied in the cart from two vials upward, and shipping is free and tracked over $200 CAD. The rest of the class is on the growth hormone secretagogues page.

All compounds referenced here are supplied by ExoLabz for laboratory research use only. They are not for human or veterinary use, are not authorised by Health Canada as a drug or natural health product, and nothing on this page is guidance on preparation, administration or use.

To see CJC-1295 without DAC next to sermorelin and tesamorelin, read our GHRH analog comparison. Every other side-by-side guide is listed under peptide comparisons.