CJC-1295 with DAC
Long-acting GHRH analog with Drug Affinity Complex
Overview
CJC-1295 with DAC is the long-acting variant of the Modified GRF 1-29 family, carrying a maleimido-propionyl group at Lys30 that allows covalent reaction with Cys34 of serum albumin in vivo, the Drug Affinity Complex (DAC) mechanism. The albumin conjugation dramatically extends plasma half-life from roughly 30 minutes (no-DAC) to approximately 6-8 days, supporting once-weekly dosing schedules in research and compounding contexts. Lyochem supplies CJC-1295 with DAC as the lyophilized acetate at ≥99.0% HPLC purity. The DAC variant requires more demanding analytical confirmation than the no-DAC form because the maleimido modification must be intact at the labelled position, partially hydrolyzed maleimide loses the in vivo albumin-binding activity even though it passes the standard HPLC purity gate at equivalent retention time. The release packet covers peak-integration HPLC plus ESI mass spec confirming the modified mass; intact-maleimide confirmation by reactivity assay against a reference thiol is available on request and is recommended at first-time supplier qualification. The DAC form's pharmacokinetic profile makes it more appropriate for sustained-elevation GH research and for compounding contexts where weekly dosing matters, while the no-DAC form is preferred for pulse-pharmacology research.
Who buys this, and why
GH-axis peptides ship to research labs studying somatotropic-pathway pharmacology, IGF-axis signalling, and pulse vs. sustained-elevation GH biology. Buyers qualifying a new source typically request sequence verification on the first lot, the counter-ion form (acetate by default), and stability data at −20 °C. Blends — the CJC-1295 + Ipamorelin co-formulated lot is the canonical example — are co-lyophilised rather than solution-mixed so the ratio is locked at the lyophilisation step.
Primary buyer fit: academic and contract research laboratories and research laboratories that have validated this peptide into their workflow.
Specifications
- CAS
- 863288-34-0
- Appearance
- White lyophilized powder
- Purity (HPLC)
- ≥ 99.0%
- Common vial sizes
- 2 mg, 5 mg
- MOQ
- On request
- Lead time
- 10–18 days
- Storage
- -20°C, protect from light
Documentation available on request
- Lot-specific Certificate of Analysis (CoA)
- RP-HPLC chromatogram with peak integration
- ESI-MS identity confirmation (±0.5 Da)
- Sequence verification by LC-MS/MS
- Water content by Karl Fischer
- SDS / MSDS
- Counter-ion analysis (acetate vs TFA)
- Stability at −20 °C across 12 months
- Solubility in BAC water / PBS reconstitution
Regulatory note
Sold for Research Use Only under the receiving laboratory's institutional and jurisdictional regulations. Not a finished dosage form, not labelled for human administration, and not supplied to compounding pharmacies — Lyochem's GH-axis lots are scoped to research workflows only. Buyers studying somatotropic pharmacology should specify the counter-ion form (acetate by default) and any pulse-vs-sustained study design notes at quote stage.
Frequently asked questions
What does the 'DAC' modification actually do at a molecular level?▾
DAC stands for Drug Affinity Complex, the modification is a maleimido-propionyl group attached at Lys30 of the modified GRF 1-29 backbone. In serum, the maleimide reacts covalently with the free thiol of Cys34 on human serum albumin, creating a long-circulating peptide-albumin conjugate. Albumin's plasma half-life is roughly 19 days in humans, so the conjugated peptide circulates with similar kinetics, dramatically extended from the ~30-minute half-life of the unmodified no-DAC form. This is the same in vivo bioconjugation strategy used by several approved peptide drugs in other therapeutic areas.
How should I choose between CJC-1295 with DAC and without DAC?▾
The answer is about pharmacokinetic profile, not potency. Without DAC: ~30-minute half-life, pulsatile GH-release pattern, preserves natural pulse architecture, dosing every several hours. With DAC: ~6-8 day half-life, sustained GH elevation, suppresses natural pulse architecture, dosing once weekly. For research workflows studying pulse pharmacology or natural GH-release patterns, the no-DAC form is essential because the DAC version eliminates the pulse signal. For sustained-elevation research and for compounding contexts where weekly dosing is preferable to multi-times-daily, the DAC form is the right choice.
Why is intact-maleimide confirmation an important analytical concern for the DAC form?▾
The DAC group's in vivo activity depends entirely on the maleimide remaining reactive, a hydrolyzed maleimide (which can form during storage or improper handling) loses the albumin-conjugation activity even though the molecule still passes the standard HPLC and mass-spec checks at very similar retention time and mass. The hydrolysis product is the open-ring carboxylic acid, which is chromatographically close to the intact maleimide but pharmacokinetically inactive. Reactivity assay against a reference thiol (cysteine or N-acetyl-cysteine) directly confirms the maleimide is intact, recommended at first-time supplier qualification and for any batch where stability is in question.
Related peptides
Buyers who view CJC-1295 with DAC also ask about:
CJC-1295 (no DAC)
≥99.0%Modified GRF 1-29 · GHRH analog
- CAS
- 863288-34-0
- Vial
- 2 mg–10 mg
Ipamorelin
≥99.0%Ghrelin / GHSR pathway GH-release peptide
- CAS
- 170851-70-4
- Vial
- 2 mg–10 mg
29-mer
Sermorelin
≥99.0%GHRH 1-29 fragment
- CAS
- 86168-78-7
- Vial
- 2 mg–10 mg