What is CJC-1295 (No DAC)?
CJC-1295 (no DAC) is a synthetic peptide corresponding to the first 29 residues of growth-hormone-releasing hormone (GHRH), carrying four defined amino-acid substitutions relative to the native GRF(1-29) sequence. The compound has the molecular formula C152H252N44O42, a molecular weight of approximately 3367.9 g/mol, and is catalogued under CAS number 863288-34-0. The designation "no DAC" indicates that this material lacks the Drug Affinity Complex (a maleimidoproprionic acid moiety used in the DAC-modified analog); it is therefore the unconjugated, standalone 29-residue peptide rather than an albumin-binding derivative.
The amino-acid sequence is Tyr-D-Ala-Asp-Ala-Ile-Phe-Thr-Gln-Ser-Tyr-Arg-Lys-Val-Leu-Ala-Gln-Leu-Ser-Ala-Arg-Lys-Leu-Leu-Gln-Asp-Ile-Leu-Ser-Arg, terminating in a C-terminal amide (-NH2). Compared with native human GRF(1-29), the modifications are [D-Ala2, Gln8, Ala15, Leu27]: an L-alanine to D-alanine change at position 2, asparagine to glutamine at position 8, glycine to alanine at position 15, and methionine to leucine at position 27. These substitutions are commonly described in the literature as sequence changes that alter the peptide's susceptibility to enzymatic cleavage and its handling characteristics in laboratory settings.
As a GHRH-family analog, CJC-1295 (no DAC) is used as a reference peptide in biochemical and cell-based research. It has been studied in laboratory models of GHRH-receptor binding and pituitary somatotroph signaling, where such peptides serve as tool compounds for characterizing receptor interactions in vitro. This monograph describes the material solely in a technical and encyclopedic capacity and makes no representation regarding any biological activity, physiological effect, or outcome in any organism.
Reconstitution & handling
For laboratory use, the lyophilized peptide is typically reconstituted with sterile water or bacteriostatic water to prepare a stock solution at a concentration chosen by the researcher. The diluent is generally added slowly against the wall of the vial and allowed to dissolve without vigorous agitation; gentle swirling is preferred over shaking, since excessive mechanical stress and foaming can degrade peptide chains. The 29-residue sequence is water-soluble, and clear, particulate-free solutions are the expected result of correct handling.
Once reconstituted, the solution should be handled under clean conditions and protected from repeated temperature cycling. Aliquoting the stock into single-use fractions minimizes freeze-thaw exposure and helps preserve integrity over the working period of an experiment. Any figures relating to concentration or volume are matters of laboratory record-keeping for in-vitro work; this monograph does not describe administration to humans or animals and provides no dosing, route, or protocol information.
Storage & stability
Lyophilized CJC-1295 (no DAC) is best stored at -20 C in a sealed vial, protected from light and moisture, where the dry powder is stable for extended periods. After reconstitution, solutions are typically kept refrigerated at 2-8 C for short-term laboratory use and at -20 C or lower for longer-term storage, with minimized freeze-thaw cycling. Desiccated, low-temperature, light-protected conditions are the standard laboratory practice for maintaining peptide quality over time.
How it's tested
Each lot is characterized by reversed-phase high-performance liquid chromatography (HPLC) to confirm chromatographic purity of ≥99%, and by mass spectrometry (MS) to verify identity against the expected molecular weight of approximately 3367.9 g/mol for the C152H252N44O42 composition. A certificate of analysis (COA) documenting purity and identity is available for each production lot. These analytical data support use of the material as a reference standard for in-vitro laboratory investigation only.