Hub · Peptide Quality & Verification
CJC-1295 with DAC vs without DAC: what is the difference?
CJC-1295 with DAC and the without-DAC structure compared here are different peptides (chains of amino acids, the building blocks of proteins) sharing a modified 29-amino-acid backbone (PubChem, a public chemistry database) derived from growth hormone-releasing hormone (GHRH), the signal that tells the pituitary gland, a small gland under the brain, to release growth hormone. DAC, the drug affinity complex, is one added amino acid carrying a chemical hook that bonds to albumin, a blood protein; the without-DAC peptide has neither.
01Without DACContents
Your blood carries albumin, a protein that ferries other molecules. One version of CJC-1295 was built to hook onto it, the other was not, yet both share a name. This page belongs to the hub on verifying peptide quality, where a name on a label counts as a claim to check, not a fact.
Below, the two molecules sit side by side. The CJC-1295 and ipamorelin research guide covers the wider research. How to read a certificate of analysis covers the supplier's test report for one batch, including the identity line that names the molecule.
Key facts
| Peptide family | Lab-made look-alikes (analogues) of growth hormone-releasing hormone |
|---|---|
| With DAC | 30 amino acids: the backbone plus one added lysine (an amino acid) carrying the hook (Jetté et al., Endocrinology, 2005) |
| Without DAC | 29 amino acids, no hook (PubChem); modified GRF(1-29) is the descriptive name used here, where GRF is a second name for GHRH |
| Human half-life, with DAC | Estimated at 5.8 to 8.1 days; a half-life is the time a blood level takes to fall by half (Teichman et al., Journal of Clinical Endocrinology & Metabolism, 2006) |
| Human half-life, without DAC | PubMed (a database of medical papers) search on 3 October 2026: no human estimate located |
What is CJC-1295 without DAC?
CJC-1295 without DAC is a 29-amino-acid peptide that copies the first 29 amino acids of human GHRH with four swaps: D-alanine (the mirror-image form of alanine) at position 2, glutamine at 8, alanine at 15 and leucine at 27. The swaps appear when the sequence record (the listed order of amino acids) in PubChem is set against its record for sermorelin, the unmodified GHRH(1-29). A blood enzyme, a protein that cuts other molecules, removes the first two amino acids from native GHRH (the body's own form) (Frohman et al., Journal of Clinical Investigation, 1986).
What does DAC add to CJC-1295?
DAC adds one amino acid, lysine, to the end of the 29-amino-acid chain, giving a 30-amino-acid peptide. That lysine carries a maleimide, a reactive chemical hook that bonds to a free thiol (a sulfur-bearing group) on cysteine (an amino acid) at position 34 of albumin, and the peptide was found in rat plasma (the liquid part of blood) beyond 72 hours (Jetté et al., Endocrinology, 2005). The attachment is covalent, meaning joined by a chemical bond; in a human pharmacokinetic study (how a substance moves through and leaves the body), Teichman et al. (2006) estimated a half-life of 5.8 to 8.1 days.
What is modified GRF(1-29)?
Modified GRF(1-29) describes, on this page, the four-swap backbone without the albumin-binding hook, rather than a proven unique registry name. Jetté et al. (2005) describe CJC-1295 as a tetrasubstituted form of hGRF(1-29), the human peptide, meaning four amino acids swapped, plus the hook-bearing lysine. PubChem's depositor-supplied names (names sent in by outside contributors) for the shorter structure include “CJC-1295-no DAC acetate”, with acetate being a salt form, but also conflicting “with DAC” names. Neither record makes “modified GRF” a unique name for that structure; the listed sequence matters more than the label.
Evidence limits
What is the half-life of CJC-1295 with DAC versus without DAC?
CJC-1295 with DAC had an estimated human half-life of 5.8 to 8.1 days in healthy adults (Teichman et al., 2006); this page's search did not locate a measured human value for the without-DAC backbone. PubMed, a US database of medical papers, was searched on 3 October 2026 for CJC-1295 without DAC, modified GRF(1-29), and tetrasubstituted GRF with human half-life or pharmacokinetic terms. This limited search does not prove that no study exists. Full-length native GHRH, a different, longer molecule, had a human half-life of 6.8 minutes (Frohman et al., 1986), which cannot establish the shorter modified peptide's value.
Which CJC-1295 does the Poisons Standard entry mean?
The Poisons Standard, Australia's national list that sorts medicines and poisons into schedules, names CJC-1295 with CAS No. 863288-34-0 (a registry number from the Chemical Abstracts Service) in Schedule 4, which covers prescription-only medicines, and in Appendix D, clause 5, item 7, which covers poisons for which possession without authority is illegal. That wording comes from the October 2026 instrument (the official document that holds the lists), F2026L01327, as checked on 1 October 2026 UTC (world standard time). The entry names neither “No DAC” nor “Mod GRF”, and the law alone does not show which molecule the number denotes, so this page makes no finding about either form.
PubChem pairs 863288-34-0 with the 29-amino-acid structure, yet only as depositor-supplied data on a record that also carries “with DAC” names. The hook-bearing structure carries 446262-90-4, listed from CAS Common Chemistry (an open lookup of the CAS registry). The pairing stays open, so the molecule in one lot is a question for that lot's paperwork, as what a batch or lot number lets a researcher verify explains. The CJC-1295 (No DAC) and ipamorelin reference material record lists C152H252N44O42.
Comparison
Facts supported by a published paper, a public chemical record or the Poisons Standard; open questions are marked. Three-letter codes are standard amino-acid abbreviations (Tyr is tyrosine, Lys is lysine, D-Ala is D-alanine), and -NH2 is a nitrogen-hydrogen cap on the last amino acid.
| Distinction | CJC-1295 with DAC | CJC-1295 without DAC (modified GRF(1-29) backbone) |
|---|---|---|
| Sequence (PubChem) | Tyr-D-Ala-Asp-Ala-Ile-Phe-Thr-Gln-Ser-Tyr-Arg-Lys-Val-Leu-Ala-Gln-Leu-Ser-Ala-Arg-Lys-Leu-Leu-Gln-Asp-Ile-Leu-Ser-Arg-Lys(3-maleimidopropionyl)-NH2 | Tyr-D-Ala-Asp-Ala-Ile-Phe-Thr-Gln-Ser-Tyr-Arg-Lys-Val-Leu-Ala-Gln-Leu-Ser-Ala-Arg-Lys-Leu-Leu-Gln-Asp-Ile-Leu-Ser-Arg-NH2 |
| Molecular formula (atoms in one molecule) and molar mass (mass of one mole, a fixed count of molecules; g/mol means grams per mole) (PubChem) | C165H269N47O46; 3647.2 g/mol | C152H252N44O42; 3367.9 g/mol |
| Albumin-binding hook | Yes: 3-maleimidopropionyl on lysine (Jetté et al., 2005) | None |
| Human half-life in the literature | Estimated 5.8 to 8.1 days (Teichman et al., 2006) | No measured human value located in the 3 October 2026 PubMed search |
| Registry (CAS) number in public records | 446262-90-4 (CAS Common Chemistry, listed in PubChem) | 863288-34-0 on PubChem's 29-amino-acid record, as depositor-supplied data; pairing unresolved |
| Named by the Poisons Standard entry (checked 1 October 2026 UTC) | Not stated: the entry names CJC-1295 only | Not stated: no “No DAC” or “Mod GRF” wording |
FAQ
Is the half-life of CJC-1295 without DAC known?
The PubMed queries recorded on 3 October 2026 did not identify a human half-life measurement for the without-DAC structure. The estimate of 5.8 to 8.1 days is for the DAC-bearing peptide (Teichman et al., 2006).
What does DAC stand for?
DAC stands for drug affinity complex. In CJC-1295 it is a reactive group on an added lysine that bonds the peptide to albumin (Jetté et al., Endocrinology, 2005).
Does the Poisons Standard say whether CJC-1295 means the with-DAC or without-DAC form?
The October 2026 Poisons Standard instrument, F2026L01327, checked on 1 October 2026 UTC, lists CJC-1295 (CAS No. 863288-34-0) in Schedule 4 and Appendix D, clause 5, item 7. The wording does not say which form it covers.
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Peptide Quality & VerificationHow research peptide material is tested, what a certificate of analysis actually records, and how a buyer checks that a vial matches its paperwork. Every article in this hub is about verification, not about use.
Citations
3 sourcesTeichman SL, Neale A, Lawrence B, Gagnon C, Castaigne JP, Frohman LA. Journal of Clinical Endocrinology & Metabolism. 2006;91(3):799-805.
doi:10.1210/jc.2005-1536Jetté L, Léger R, Thibaudeau K, et al. Endocrinology. 2005;146(7):3052-3058.
doi:10.1210/en.2004-1286Frohman LA, Downs TR, Williams TC, Heimer EP, Pan YC, Felix AM. Journal of Clinical Investigation. 1986;78(4):906-913.
doi:10.1172/JCI112679
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CJC-1295 (No DAC) & Ipamorelin reference material — batch COA includedMore on peptide quality & verificationForm Laboratories supplies research-use-only reference material. This article is an educational summary of published third-party literature. It is not medical advice, not a use instruction, and research material is not for human or animal use.