Research comparison
CJC-1295 with DAC vs without DAC
CJC-1295 is a synthetic analogue of growth-hormone-releasing hormone (GHRH 1-29), studied in laboratory models of the GH/IGF-1 axis. The two forms differ by a single structural addition — the Drug Affinity Complex (DAC) — and that one change is what separates a long-acting research compound from a short-acting one. This page compares the two forms on the objective properties researchers actually select between.
Side by side
| CJC-1295 with DAC | CJC-1295 without DAC | |
|---|---|---|
| Peptide class | GHRH (1-29) analogue | GHRH (1-29) analogue (modified GRF 1-29) |
| Structural difference | Carries the Drug Affinity Complex (binds serum albumin) | No DAC — the stabilised GRF 1-29 backbone only |
| Reported half-life | Extended — on the order of days | Short — on the order of minutes |
| GH-release profile in models | Sustained elevation ('bleed') | Pulsatile, closer to native GHRH kinetics |
| Molecular weight | Higher (DAC adds mass) | Lower |
How they differ in research
The only functional difference is the DAC. It is a small chemical group that binds to serum albumin, which in research models dramatically lengthens how long the molecule persists before clearance — turning a compound with a minutes-scale half-life into one measured in days.
That single change alters the shape of GH secretion observed in models: the DAC form is studied for a sustained elevation of GH and downstream IGF-1, whereas the no-DAC form produces a shorter, more pulsatile pattern that more closely resembles endogenous GHRH signalling.
Because the backbone is otherwise identical, the two are frequently used as a matched pair in research comparing sustained versus pulsatile GHRH-analogue exposure.
Which suits which research question
Choose the no-DAC form when a research design calls for short, pulsatile GHRH-analogue exposure that mimics native kinetics; choose the DAC form when the design calls for sustained exposure over a longer window. Both are supplied as lyophilised research compounds for in-vitro laboratory use only.
Frequently asked questions
What does DAC stand for in CJC-1295?
DAC is the Drug Affinity Complex — a chemical group added to the CJC-1295 backbone that binds to serum albumin. In research models this greatly extends the compound's half-life compared with the version that lacks it.
Is CJC-1295 without DAC the same as modified GRF 1-29?
Yes. 'CJC-1295 without DAC' and 'modified GRF 1-29' refer to the same tetra-substituted GHRH (1-29) sequence — the stabilised backbone without the albumin-binding DAC group.
Which form has the longer half-life?
The DAC form. Albumin binding via the DAC is what extends its persistence in research models to a scale of days, versus minutes for the no-DAC form.
This comparison describes objective compound pharmacology reported in the research literature. It is not medical guidance and makes no human efficacy, dosing, or therapeutic claims. All products are supplied by CertaPeptides (CERTALAB S.R.L.), a reseller, for laboratory research use only — not for human or animal consumption.