GH axis research
Work comparing modified and unmodified GRF analogues, where the DAC and the counter-ion are both variables under study rather than details.
Peptide · Growth hormone axis
CJC-1295 with DAC
The drug-affinity-complex form of CJC-1295 — a different molecule from the plain peptide, with a different counter-ion, and the product whose documentation is most often mixed up in this catalogue.
Also known as CJC-1295 DAC · CJC-1295 · GRF(1-29) with DAC · DAC:GRF
Overview
What CJC-1295 with DAC is
CJC-1295 with DAC is a GRF(1-29) analogue carrying a maleimidopropionic acid drug-affinity complex. The DAC is the point of the molecule: it is what the “with DAC” in the name refers to, and it is why this product is not interchangeable with the CJC-1295 listed a few lines below it in our catalogue.
The two differ in mass, in counter-ion and in how they are handled. Our batch of the DAC form is the trifluoroacetate salt, with 18.3% TFA and a peptide content of 84.5%. The non-DAC product is a different specification entirely. If a quotation is headed “CJC-1295” without saying which of the two it is, the quote is ambiguous and should be treated that way.
We publish this page without a CAS number, molecular formula or sequence, because the certificate for the batch we hold does not print them. Those values are available with the quotation, and we would rather leave a field empty than fill it from memory — a CAS number that cannot be tied to a document is worse than no number at all.
- 98.6% by HPLC; largest single impurity 0.4%
- Trifluoroacetate salt — 18.3% TFA, acetic acid not detected
- Peptide content 84.5%, water 3.9%, both stated separately
- Distinct from CJC-1295 without DAC (ES005) — different molecule, different documentation
Identity
The record.
The identifiers your specification sheet, customs paperwork and product label all have to agree on. Where a number depends on the salt form, both are given.
- Chemical name
- GRF(1-29) analogue with drug-affinity complex, TFA salt
- Common name
- CJC-1295 with DAC; DAC:GRF
- CAS number
- Not printed on this batch's certificate — supplied on request
- Molecular formula
- Not printed on this batch's certificate
- Molecular weight
- Not printed on this batch's certificate
- Residue count
- GRF(1-29) backbone, DAC-modified
- Counter-ion
- Trifluoroacetate, 18.3% on the current lot
- Appearance
- White or almost white powder
- Solubility
- Soluble in water
- Water content
- ≤ 8.0% (Karl Fischer)
- Peptide content
- 84.5% (nitrogen determination)
- Storage
- −20 ± 5 °C, sealed, protected from light
HS codes are indicative only. Final classification is confirmed per shipment with your customs broker.
Manufacture
How it is made.
The peptide is the easy half. Attaching the DAC and removing the trifluoroacetate are the steps that decide what you receive.
- 01
Solid-phase assembly
The GRF(1-29) backbone is assembled on resin, then modified to carry the maleimidopropionic acid linker that defines the DAC form.
- 02
Conjugation
The DAC is attached through the linker. Incomplete conjugation leaves unmodified peptide in the batch — a closely related impurity that purification has to resolve.
- 03
Purification
Reversed-phase HPLC against the conjugated product. The largest single impurity of 0.4% on this lot reflects how much unconjugated material survived.
- 04
TFA salt formation and drying
The peptide is supplied as the trifluoroacetate. TFA is a strong ion-pairing acid that improves chromatography and solubility; it is also the reason this product cannot be treated as interchangeable with an acetate form.
Applications
Where it is used.
Supplied to laboratories studying the growth-hormone axis with an extended-half-life analogue. Research use only.
Half-life studies
The DAC form is used where the conjugation chemistry itself is the subject, since the linker is what changes the pharmacokinetic behaviour.
Analytical development
A useful case for methods that must distinguish conjugated from unconjugated peptide — the impurity that matters here is a near-neighbour, not a truncation.
Specification
Release criteria.
The written limits we release against, with the method used to test each one. Batch results for the lot you receive are stated on its certificate of analysis.
| Parameter | Limit | Method |
|---|---|---|
| Appearance | White or almost white powder | Visual |
| Solubility | Soluble in water | Visual |
| Water content | ≤ 8.0% | Karl Fischer |
| Acetic acid | ≤ 0.25% | HPLC |
| Trifluoroacetic acid | ≤ 25.0% | HPLC |
| Purity | ≥ 98.0% | HPLC |
| Peptide content (N) | ≥ 80.0% | Nitrogen determination |
| Largest single impurity | ≤ 1.0% | HPLC |
| Bacterial endotoxin | < 10 EU/mg | LAL |
| Shelf life | 24 months from manufacture | Stability programme |
Tighter limits — for example a lower heavy-metal ceiling or a residual-solvent panel — can be quoted against your own specification wording.
Certificate
Reading the certificate.
This is the product where a certificate most often describes the wrong molecule, because the catalogue names are too similar.
Confirm the code, not just the name
ED0003 is the DAC form; ES005 is CJC-1295 without DAC. They have different masses, different counter-ions and different specifications. A certificate headed with the name alone cannot be matched to an order.
TFA at 18.3% is a fact you have to plan for
A high trifluoroacetate load lowers peptide content and introduces an acid that is not inert in every assay. If your protocol is sensitive to residual TFA, this is a specification to discuss before ordering rather than after.
Peptide content 84.5%, not 98.6%
The purity figure describes the peptide fraction of the organic material; the peptide content describes how much of the powder is peptide. With 18.3% TFA and 3.9% water, a 10 mg weighing holds about 8.5 mg of peptide.
Documentation & packaging
What ships with it.
The paperwork travels with the goods. If your QA team needs an extra declaration, ask before the order is released — some are issued per production lot and cannot be retrofitted.
Certificate of analysis
Purity, TFA content, water, peptide content, largest single impurity and endotoxin for the lot supplied.
Specification sheet
The enterprise standard the batch is released against, including the TFA limit.
Identity data
Mass spectrometry data, and the CAS number and molecular formula on request where the batch certificate does not print them.
SDS
Issued on request — this product does not currently ship with a safety data sheet in the pack.
| Pack size | Presentation | Typical use |
|---|---|---|
| 1–10 g | Amber vial, 10 mL | Evaluation |
| 25–50 g | Amber vial, 50 mL | Pilot scale |
| 100 g | Amber vial, 100 mL | Small commercial |
| 1 kg+ | Foil bag, quoted per order | Bulk |
Questions
Before you order.
The questions buyers actually ask about CJC-1295 with DAC. Anything not covered here, ask directly — you will get an answer from someone technical, not a template.
What does “with DAC” actually mean?
DAC is a drug-affinity complex — a maleimidopropionic acid linker that lets the peptide associate with albumin. It is the defining modification of this product and the reason it is a different molecule from CJC-1295 without DAC, not a variant of it.
Why is there no CAS number on this page?
Because the batch certificate we hold does not print one. The value is available with your quotation. Publishing an identifier we cannot tie to a document would make the page easier to read and less true, and this catalogue is built the other way round.
Why is the counter-ion TFA rather than acetate?
This product is supplied as the trifluoroacetate salt, at 18.3% on the current lot. That is a property of the material we hold, not a preference — if you need an acetate form, it would be a made-to-order item and should be specified before quoting.
Is 18.3% TFA normal?
It is high but it is real, and it is stated on the certificate. Trifluoroacetate load varies with the peptide's charge and the salt-exchange step. The practical consequence is a peptide content of 84.5% — use that number for weighing, not the purity.
Can this be substituted for CJC-1295 without DAC?
No. Different molecule, different mass, different counter-ion, different documentation. If a study or a specification calls for one, the other is not a substitute, and a supplier who treats them as interchangeable is telling you something about their catalogue control.
How should it be stored and shipped?
−20 ± 5 °C, sealed and protected from light. This is the one product in the range where we specify frozen storage rather than 2–8 °C — follow the certificate, not a generic assumption.
Related
Often quoted together.
Quotation
Ask for CJC-1295 with DAC, by the gram.
Send the quantity, the grade you need and the destination. You will get a written quotation with lead time, packaging options and the documentation set for this material.