How to Reconstitute CJC-1295 Without DAC: Step-by-Step Lab Protocol

CJC-1295 without DAC (Modified GRF 1-29, Mod GRF 1-29, MW 3367.9 g/mol) is a stabilised synthetic GHRH analogue incorporating four amino acid substitutions — Ala2→D-Ala, Gln8→Ala, Ala15→Ala, Leu27→Leu — that confer resistance to DPP-IV and endopeptidase cleavage without the drug affinity complex (DAC) albumin-binding modification found in CJC-1295 with DAC. It is supplied as a lyophilised white powder in a 10mL sterile glass vial containing 2mg of peptide. Proper reconstitution ensures accurate working concentrations for GHRH-R receptor pharmacology and GH axis cell model research.

Materials Required

  • CJC-1295 No DAC 2mg lyophilised vial
  • Bacteriostatic water (BAC water) — 10mL vial
  • 1mL sterile syringe with needle
  • Alcohol swabs (70% isopropyl)
  • Nitrile gloves
  • Permanent marker for labelling
  • Refrigerator at 2–8°C for storage

Pre-Reconstitution Preparation

Inspect the vial to confirm the lyophilised powder is intact and the seal is unbroken. Remove from cold storage and allow to equilibrate to room temperature for 10 minutes before reconstitution. CJC-1295 No DAC is a 29-amino acid peptide that dissolves readily — the equilibration step is primarily to prevent condensation entering the vial rather than to aid dissolution.

Step-by-Step Reconstitution Protocol

Step 1 — Prepare workspace. Clean the work surface with 70% isopropyl alcohol. Allow to dry completely. Wear nitrile gloves throughout.

Step 2 — Swab both stoppers. Wipe the rubber stopper of both the CJC-1295 vial and the BAC water vial with separate fresh alcohol swabs. Air dry for 10 seconds each.

Step 3 — Draw 1mL of BAC water. Using a sterile syringe, draw 1mL of bacteriostatic water. For a 2mg vial, 1mL yields a practical stock concentration of 2mg/mL that simplifies dilution calculations for cell model assay preparation.

Step 4 — Inject slowly along the vial wall. Angle the needle tip against the inner glass wall of the CJC-1295 vial and inject the BAC water in a slow, controlled stream down the glass over 10–15 seconds. Avoid directing the stream onto the lyophilised powder.

Step 5 — Dissolve gently. Gently swirl the vial for 20–30 seconds. CJC-1295 No DAC dissolves readily and the solution should become clear and colourless quickly. Do not shake or vortex.

Step 6 — Inspect and label. Confirm the solution is fully clear. Label with reconstitution date, concentration, and initials.

Resulting Concentration

Adding 1mL BAC water to a 2mg CJC-1295 No DAC vial yields a stock concentration of 2mg/mL (2000mcg/mL). For GHRH-R cAMP accumulation assays and GH3 somatotroph cell model studies, working concentrations of 1nM–100nM are prepared by serial dilution into assay buffer or serum-free media.

Concentration Reference Table

BAC Water Volume AddedResulting Concentration
1mL2.0mg/mL (2000mcg/mL)
2mL1.0mg/mL (1000mcg/mL)

Storage Conditions and Stability

Store lyophilised CJC-1295 No DAC at −20°C prior to reconstitution, protected from light. Once reconstituted, store at 2–8°C. Reconstituted solution is stable for up to 28 days under refrigeration. Do not freeze reconstituted solution. Unlike CJC-1295 with DAC, the No DAC version does not bind albumin, so its free concentration in serum-containing media accurately reflects the nominal concentration — an advantage for precise concentration-response pharmacology studies. For long-term aliquot storage prepare single-use microcentrifuge aliquots and store at −80°C.

Research Application Notes

CJC-1295 No DAC's four stabilising amino acid substitutions confer resistance to DPP-IV and endopeptidase cleavage, making it significantly more stable than native GHRH(1-29) (sermorelin) in serum-containing cell culture media. This stability advantage makes it suitable for longer-duration GHRH-R activation studies without DPP-IV inhibitor supplementation. In comparative GHRH-R pharmacology assays, CJC-1295 No DAC and sermorelin provide complementary data on native versus stabilised GHRH analogue pharmacology at the same receptor. Unlike CJC-1295 with DAC, the No DAC version produces pulsatile rather than sustained GHRH-R activation, which is an important distinction for cell model research protocol design. CJC-1295 No DAC 2mg vials are available from Pinnacle Peptides, verified at ≥99% purity by HPLC and mass spectrometry.

All content is intended for in vitro laboratory research purposes only. Not for human or animal consumption. Not intended to diagnose, treat, cure, or prevent any condition.