CJC-1295 with DAC Reconstitution Guide
Part of the full CJC-1295 with DAC guide - a synthetic growth-hormone-releasing hormone reference compound, identity-verified with a COA on every vial.
In brief
This spoke describes laboratory reconstitution of lyophilized CJC-1295 with DAC for in-vitro research handling only. It is not a dosing protocol and contains no human-use guidance. Like other lyophilized research peptides, CJC-1295 with DAC is typically supplied as a freeze-dried solid that must be brought into solution before any benchtop assay. The standard diluent for research reconstitution is bacteriostatic water (sterile water containing roughly 0.9 percent benzyl alcohol), which resists microbial growth across repeated aspirations from a multi-use vial. The governing principle is simple: the mass of peptide in the vial is fixed, so the concentration of the resulting stock solution is set entirely by the volume of diluent added. Choosing that volume deliberately, calculating the resulting concentration, and storing the stock under conditions that protect a maleimide-bearing albumin-binding peptide are the three pillars of sound in-vitro preparation.
The detail
A closer look
01
Concentration math for stock preparation
Concentration follows directly from mass divided by volume. For a vial containing a stated mass of CJC-1295 with DAC, the stock concentration equals that mass divided by the volume of bacteriostatic water added. As a worked example using round numbers, dissolving a 5 mg vial in 2 mL of bacteriostatic water yields 2.5 mg/mL, while the same 5 mg in 1 mL yields 5 mg/mL; halving the diluent doubles the concentration. Smaller diluent volumes give a more concentrated stock that requires less material per assay but leaves less margin for pipetting error, whereas larger volumes ease accurate aliquoting at the cost of a more dilute stock. Because the molecule's free pre-conjugation mass is cited near 3647 g/mol, that figure can be used to convert a mass-based stock into molarity for in-vitro work where a molar working concentration is required for receptor or conjugation assays.
02
Stability-aware handling for a maleimide DAC peptide
Two structural features of this molecule warrant careful handling. First, the C-terminal Nepsilon-maleimidopropionyl group is the reactive warhead that forms the thioether bond to albumin Cys34; maleimides react with free thiols, so reconstituted stock should be kept away from thiol-containing additives unless that conjugation is the intended experiment. Second, as a 30-residue peptide it benefits from the general cold-chain discipline applied to research peptides. Reconstituted stock is conventionally held refrigerated for near-term work and frozen for longer storage, with repeated freeze-thaw cycles minimized to limit aggregation and degradation. Aliquoting the stock into single-use fractions before freezing avoids subjecting the whole batch to repeated temperature swings. Vials should be returned to cold storage promptly and labeled with concentration and date so that downstream molarity calculations remain traceable for the lab record.
Step by step
How CJC-1295 with DAC is reconstituted
A bench reference for handling and preparation in an in-vitro research setting. Not a personal dosing protocol.
- 1
Allow the sealed lyophilized vial and the bacteriostatic water to equilibrate to room temperature before opening, and wipe both stoppers with an alcohol swab.
- 2
Decide the target stock concentration and compute the diluent volume as vial mass divided by desired concentration (for example, 5 mg at a 2.5 mg/mL target requires 2 mL).
- 3
Draw the calculated volume of bacteriostatic water into a sterile syringe.
- 4
Inject the water slowly down the inner wall of the vial rather than directly onto the lyophilized cake to limit foaming and shear on the peptide.
- 5
Do not shake; swirl gently or let the vial stand until the solid fully dissolves into a clear solution.
- 6
Record the final concentration on the vial label, optionally converting to molarity using the cited ~3647 g/mol pre-conjugation mass.
- 7
Aliquot into single-use fractions to minimize repeated freeze-thaw of the full batch.
- 8
Store refrigerated for near-term in-vitro use or frozen for longer-term storage, keeping the reactive maleimide away from unintended thiol-bearing reagents.
The fine print: products are sold for laboratory research use only and are not for human or animal consumption. Bodily introduction into humans or animals is strictly prohibited by law. CJC-1295 with DAC is not a drug and is not intended to diagnose, treat, cure, or prevent any disease. These statements have not been evaluated by the FDA.