Which covalent structures are sold under the name CJC-1295?
CJC-1295, as identified in the peptide-chemistry literature, is a synthetic analogue of human growth-hormone-releasing factor residues 1–29 (GRF(1–29)) that is covalently elaborated so it can form an albumin bioconjugate. Jetté and co-workers described human GRF(1–29)–albumin bioconjugates and identified CJC-1295 as the long-lasting GRF analogue arising from that design. For a purchasing laboratory the operational meaning is structural: the reagent is defined by a GRF(1–29)-derived sequence, typically with substitutions that reduce proteolytic clipping, an additional residue that presents a conjugation handle, and a maleimide-containing Drug Affinity Complex (DAC) linker—commonly a maleimidopropionyl group—intended to react with a free thiol on albumin.
Those layers create three catalogue species that are routinely conflated. The first is DAC-bearing CJC-1295 as a free, unconjugated peptide: the maleimide is intact and the intact mass includes the linker. The second is the same sequence after maleimide hydrolysis or thiol capping, which is no longer albumin-reactive and will not match the theoretical mass of the intact DAC form. The third is tetrasubstituted GRF(1–29) without any DAC, often listed as 'CJC-1295 without DAC' or 'modified GRF 1–29'. A purchase order that states only 'CJC-1295' does not distinguish these covalent structures.
A research specification should therefore lock the intended species in writing. Minimum identity fields are: full amino-acid sequence; C-terminal amide or acid; explicit DAC present or DAC absent; chemical description of the linker if present; theoretical monoisotopic and average masses for that structure; and salt form (acetate versus trifluoroacetate). If the laboratory requires an unreacted maleimide, the specification should state that the linker has not been quenched. Sequence, linker status and theoretical mass are not optional labels; they are what make the catalogue string a defined chemical. Copy sequence, linker status and theoretical mass onto the goods-in specification used at receiving.
How should HPLC-MS distinguish CJC-1295 from related GHRH analogues?
Identity confirmation for a synthetic GHRH analogue is an intact-mass plus chromatographic-purity problem. Reversed-phase HPLC with ultraviolet or diode-array detection separates the principal peak from deletion sequences, incomplete coupling products and linker-related impurities. The purity figure on a certificate of analysis is only interpretable if the method is identified—column chemistry, gradient and detection wavelength—and if a chromatogram with a labelled principal peak is supplied. Peak-area percent at a single wavelength is not a structure assignment.
Mass spectrometry supplies the structure-sensitive half of the pair. Electrospray ionisation of a DAC-bearing analogue of this size typically yields a charge-state envelope; deconvolution should recover a mass consistent with the stated sequence plus linker, within the instrument’s stated mass-accuracy window. A DAC-free tetrasubstituted GRF(1–29) deconvolutes to a lower mass. A hydrolysed maleimide sits a water-addition increment above the intact maleimide. Those mass differences are the test that a catalogue name cannot provide.
Henninge and co-workers identified CJC-1295 in an unknown pharmaceutical preparation, showing that undeclared products can contain the analogue and that identification rests on analytical data rather than packaging claims. For a research buyer the procedural lesson is to request the mass spectrum, not only a printed identity line. Where sequence confirmation is required, tandem-MS fragment ions or peptide mapping should be specified. Immunoaffinity purification followed by liquid chromatography–mass spectrometry is a published route for isolating peptide hormones before MS in complex matrices; a lyophilised research vial is a simpler matrix, so the same identity logic applies with less enrichment: match intact mass, inspect the isotope envelope, and exclude the DAC-free and linker-hydrolysis masses explicitly.
Related analogues that a selective method must not conflate with DAC-bearing CJC-1295 include unmodified GRF(1–29), tetrasubstituted GRF(1–29) without DAC, and N-acylated GHRH analogues that carry a different covalent tag. Selectivity is demonstrated when masses or retention times resolve those species, not when the CoA repeats the catalogue string.
What should you verify when you buy CJC-1295 Australia?
A certificate of analysis is a batch record. Before an Australian laboratory places an order, the CoA template—or a redacted example from a recent lot—should be checked against fields that can be reconciled with the vial that will arrive.
Identity block: peptide name with DAC status stated, sequence, theoretical mass, observed mass, and technique (ESI-MS, MALDI-TOF or LC-MS). Observed mass without a technique is incomplete. Purity block: HPLC purity as area percent, a chromatogram with the principal peak labelled, a method identifier, and integration parameters. A purity number with no chromatogram cannot be audited. Quantity block: vial contents on a net-peptide basis, with the method named (amino-acid analysis, nitrogen determination or a calibrated HPLC assay). Counter-ion and residual water, if reported, should name the method—ion chromatography or fluorine NMR for trifluoroacetate; Karl Fischer titration for water. Appearance and lot number must match the vial label and the dispatch note.
Traceability block: release date, a retest date recorded as a documentation field, and a unique lot code on every page of the analytical packet. For multi-vial orders, all vials should share that lot code, or each lot should have its own full packet. Local Australian stock matters because the receiving laboratory can match a domestic lot code to the CoA without an extra import hop that severs the paper trail. Tracked dispatch links the released lot to the parcel.
Research-use framing should be explicit on the CoA and the label: material supplied for laboratory research only, not as a therapeutic good, and not for human or veterinary use. That statement does not replace analytical fields. If identity, purity chromatogram, observed mass, lot code or net-peptide basis is missing, the purchasing action is to withhold the order until the packet is complete. Paying for a catalogue name without those fields is not a cheaper reagent; it is an uncharacterised powder.
Which orthogonal methods in the literature support identity confirmation?
Published identification methods for CJC-1295 and related GHRH analogues were developed largely in residue-analysis settings, where the analytical question matches the one a research laboratory should ask of a vial: is this covalent structure present, and can it be distinguished from neighbouring analogues?
Timms and co-workers described an immuno-polymerase chain reaction screen for CJC-1295 and other GHRH analogues in equine plasma, using antibody capture to raise selectivity before detection. The same group reported a liquid chromatography–tandem mass spectrometry confirmatory method for CJC-1295 in equine plasma. Pont and co-workers compared magnetic-bead surface chemistries for immunopurification of growth-hormone-releasing hormones before liquid chromatography–high-resolution mass spectrometry. Thomas and co-workers summarised immunoaffinity purification of peptide hormones before LC-MS in doping-control workflows.
A research-peptide buyer is not running plasma residue methods on incoming vials, but the method hierarchy transfers. Binder-based screens can flag a GHRH-class peptide and still mis-assign DAC status or sequence substitutions. Confirmation requires a mass-selective method with defined precursor and product ions, or high-resolution intact mass plus fragment coverage. Magnetic-bead immunopurification is relevant when a laboratory later recovers the reagent from a biological matrix; it is not a substitute for release testing of the neat lyophilised solid.
For incoming-goods control the proportionate orthogonal pair is reversed-phase HPLC for purity and retention-time consistency, plus intact-mass MS for identity. A third method—amino-acid analysis, peptide mapping, or tandem-MS sequence tags—is justified when the lot will be used as a reference material or when DAC versus DAC-free catalogue descriptions must be settled. Acceptance criteria should be written before data are collected: a mass-agreement window, a maximum unidentified peak area, and a requirement that the DAC-free mass is below a stated threshold if the specification is DAC-bearing.
How should impurity data and Australian supplier documents guide a purchase?
Purchase decisions should treat the impurity profile as part of identity. For a DAC-bearing GRF analogue the characteristic process impurities follow from solid-phase synthesis and from maleimide chemistry. Deletion and truncated sequences appear as earlier-eluting RP-HPLC peaks and as masses reduced by one residue. Residual protecting groups appear at higher mass. Incomplete DAC incorporation yields a peak at the DAC-free mass—the related substance that must be quantified if the specification requires an albumin-reactive maleimide. Maleimide hydrolysis adds water to the linker and removes thiol reactivity; it is neither the intact DAC form nor the DAC-free peptide and should be listed as a named related substance when the reactive handle matters. Counter-ion is a specification field: trifluoroacetate from preparative HPLC is common; acetate after exchange is a different material on a mass-balance basis. Net peptide content changes with counter-ion and residual water, so two vials with the same nominal contents are not comparable unless the CoA states the basis. A single HPLC purity of greater than 98 percent does not disclose whether residual area is DAC-free analogue, a deletion peptide, or an unidentified peak. Ask for a related-substance table with relative retention times and assigned masses where MS was used.
Supplier evaluation for an Australian laboratory is then a documentation and logistics audit of those data. Ask who performed the HPLC and MS: in-house, a named contract laboratory, or an unnamed party. Ask whether the chromatogram belongs to the lot on the vial or to a 'representative' lot; representative data are not lot data. Ask whether sequence confirmation is theoretical from the synthesis record or measured. Compare principal-peak purity, observed mass, counter-ion and the DAC-free related-substance level across lots if continuity matters. For multi-vial orders, one lot with one packet is analytically cleaner than mixed lots on one invoice. Local stock, tracked dispatch and lot codes that match the CoA complete chain of custody.
The material is a research chemical, not a medicine or veterinary product. Published identification of CJC-1295 in an undeclared preparation is a reminder that grey-market labelling is a known failure mode. Receiving checks—lot-code inspection, CoA filing, and quarantine until the specification is met—convert the query into a cited reagent.
Order Cjc 1295 with documentation
If this guide helped you evaluate Cjc 1295 for laboratory work, the next step is documented supply: research-grade stock from Australian warehouses, Express tracked shipping, and batch documentation with every order.
Open the Cjc 1295 card on the ClaraScience shop for current stock and add-to-cart, or request wholesale access when you need bulk restocks and tier pricing.
Frequently asked questions
Is CJC-1295 the same reagent as modified GRF 1–29?
No. Modified GRF 1–29 is a tetrasubstituted GRF(1–29) analogue without a Drug Affinity Complex (DAC) maleimide linker. CJC-1295 in the chemistry literature is the DAC-bearing, albumin-reactive construct. Intact-mass HPLC-MS is the practical distinction. Specify DAC status on the purchase order and require theoretical and observed masses for that structure. A catalogue name alone does not identify the covalent species in the vial.
What mass-spectrometric evidence should a CoA include?
At minimum, the theoretical mass for the stated sequence and linker, the observed deconvoluted mass, the ionisation mode, and a spectrum or peak list. A pass/fail identity line without a mass is not auditable. If DAC is specified, the CoA should show that the DAC-free mass was considered and is not the principal component.
Does local Australian stock change the analytical packet?
Local stock does not change HPLC-MS acceptance criteria, but it does change traceability. Lot codes on vials can be matched to a CoA and a tracked dispatch record without an extra import step that can separate paperwork from the physical lot. Require every vial in the shipment to carry the lot number printed on the CoA.
Can an immunoassay replace HPLC-MS for incoming identity?
Antibody-based screens can indicate a GHRH-class peptide and still miss DAC status or sequence substitutions. Published immuno-PCR and immunopurification methods are paired with mass-spectrometric confirmation for that reason. For a lyophilised research vial, reversed-phase HPLC plus intact-mass MS remains the proportionate identity pair.
What research-only statement should appear on the label?
The material should be labelled for laboratory research only, not as a therapeutic good and not for human or veterinary use. That statement sits beside, and does not replace, sequence, mass, purity chromatogram and lot code. Procurement should stop if the analytical fields are missing, regardless of disclaimer text.
References
- PMID:15817669 — Human growth hormone-releasing factor (hGRF)1-29-albumin bioconjugates activate the GRF receptor on the anterior pituitary in rats: identification of CJC-1295 as a long-lasting GRF analog — Endocrinology — 2005
- PMID:21204297 — Identification of CJC-1295, a growth-hormone-releasing peptide, in an unknown pharmaceutical preparation — Drug Test Anal — 2010
- PMID:21871962 — Immunoaffinity purification of peptide hormones prior to liquid chromatography-mass spectrometry in doping controls — Methods — 2012
- PMID:30489688 — An immuno polymerase chain reaction screen for the detection of CJC-1295 and other growth-hormone-releasing hormone analogs in equine plasma — Drug Test Anal — 2019
- PMID:30938069 — A method for confirming CJC-1295 abuse in equine plasma samples by LC-MS/MS — Drug Test Anal — 2019
- PMID:32971474 — Comparison of magnetic bead surface functionalities for the immunopurification of growth hormone-releasing hormones prior to liquid chromatography-high resolution mass spectrometry — J Chromatogr A — 2020
Research use only
This article is provided for laboratory research and educational purposes only. Products referenced are not for human or veterinary use. ClaraScience makes no therapeutic, medical, or efficacy claims, and nothing here constitutes medical advice.
