Cosmic Peptides research library

Sermorelin and CJC-1295 (no DAC) compared

How Sermorelin and CJC-1295 (no DAC) differ in structure, calculated properties and analysis: the sequences aligned, the mass difference, and how mass spectrometry and HPLC tell them apart.

Last reviewed · Editorial policy

Both are 29-residue C-terminal amides built on the first 29 residues of growth hormone–releasing hormone. CJC-1295 without DAC carries four substitutions in that chain; sermorelin is the unmodified sequence.

Sequences side by side

Aligned from residue 1: 25 positions identical, 4 substituted. In each column the upper residue is Sermorelin's and the lower is CJC-1295 (no DAC)'s. Substituted positions are highlighted.

#SermorelinCJC-1295 (no DAC)
1TyrTyr
2AlaD-Ala
3AspAsp
4AlaAla
5IleIle
6PhePhe
7ThrThr
8AsnGln
9SerSer
10TyrTyr
11ArgArg
12LysLys
13ValVal
14LeuLeu
15GlyAla
16GlnGln
17LeuLeu
18SerSer
19AlaAla
20ArgArg
21LysLys
22LeuLeu
23LeuLeu
24GlnGln
25AspAsp
26IleIle
27MetLeu
28SerSer
29ArgArg

Both have the same termini: free amine and amide.

Calculated properties

Calculated from each structure
PropertySermorelinCJC-1295 (no DAC)Difference (CJC-1295 (no DAC) − Sermorelin)
Residues29290
Molecular formulaC149H246N44O42SC152H252N44O42
Monoisotopic mass (Da)3,355.81873,365.8936+10.0749
Average mass (g/mol)3,357.933,367.95+10.02
Net charge at pH 74.04.00.0
Isoelectric point10.9510.950.00
Hydropathy (GRAVY)-0.22-0.08+0.14
ε280 (M−1 cm−1)2,9802,980

Telling them apart by mass spectrometry

The monoisotopic masses differ by 10.0749 Da, which any routine mass spectrometer resolves.

Expected protonated ions (monoisotopic m/z)
IonSermorelinCJC-1295 (no DAC)
[M+H]+3,356.82603,366.9009
[M+2H]2+1,678.91661,683.9541
[M+3H]3+1,119.61351,122.9718
[M+4H]4+839.9620842.4807

Telling them apart by HPLC

CJC-1295 (no DAC) is the more hydrophobic by the Kyte–Doolittle average (a difference of 0.14), so in reversed-phase HPLC it would usually be expected to elute later. Retention depends on the whole molecule and on the method, so the order is confirmed by running both, or by mass spectrometry of each peak.

Analytical variants each can form

The sequence-specific variants from each entry. A variant only one of them can form is a quick way to tell which is which, and a reminder of what to look for in each.

Sequence-specific variants
VariantMass changeSermorelinCJC-1295 (no DAC)
Methionine oxidation+15.995 Da per oxidized residueYesNo
Asparagine deamidation+0.984 DaYesNo
Glutamine deamidation+0.984 DaYesYes
C-terminal amidefree-acid variant +0.984 DaYesYes
Stereochemistry0 DaNoYes

Full details, with isotope patterns and fragment ions, are on each entry: Sermorelin and CJC-1295 (no DAC). Both are compared with the rest of their family on the family page.

Sources & Further Reading

  1. Prohaska T, Irrgeher J, Benefield J, Böhlke JK, Chesson LA, Coplen TB, et al. Standard atomic weights of the elements 2021 (IUPAC Technical Report). Pure and Applied Chemistry 2022;94(5):573–600. doi:10.1515/pac-2019-0603
  2. Wang M, Huang WJ, Kondev FG, Audi G, Naimi S. The AME 2020 atomic mass evaluation (II). Tables, graphs and references. Chinese Physics C 2021;45(3):030003. doi:10.1088/1674-1137/abddaf
  3. Rice P, Longden I, Bleasby A. EMBOSS: the European Molecular Biology Open Software Suite. Trends in Genetics 2000;16(6):276–277. doi:10.1016/S0168-9525(00)02024-2
  4. Pace CN, Vajdos F, Fee L, Grimsley G, Gray T. How to measure and predict the molar absorption coefficient of a protein. Protein Science 1995;4(11):2411–2423. doi:10.1002/pro.5560041120
  5. Kyte J, Doolittle RF. A simple method for displaying the hydropathic character of a protein. Journal of Molecular Biology 1982;157(1):105–132. doi:10.1016/0022-2836(82)90515-0
  6. Meija J, Coplen TB, Berglund M, Brand WA, De Bièvre P, Gröning M, et al. Isotopic compositions of the elements 2013 (IUPAC Technical Report). Pure and Applied Chemistry 2016;88(3):293–306. doi:10.1515/pac-2015-0503
  7. Roepstorff P, Fohlman J. Letter to the editors: proposal for a common nomenclature for sequence ions in mass spectra of peptides. Biomedical Mass Spectrometry 1984;11(11):601. doi:10.1002/bms.1200111109
  8. Biemann K. Contributions of mass spectrometry to peptide and protein structure. Biomedical and Environmental Mass Spectrometry 1988;16(1–12):99–111. doi:10.1002/bms.1200160119
  9. Geiger T, Clarke S. Deamidation, isomerization, and racemization at asparaginyl and aspartyl residues in peptides. Succinimide-linked reactions that contribute to protein degradation. Journal of Biological Chemistry 1987;262(2):785–794. doi:10.1016/S0021-9258(19)75855-4
  10. Manning MC, Chou DK, Murphy BM, Payne RW, Katayama DS. Stability of protein pharmaceuticals: an update. Pharmaceutical Research 2010;27(4):544–575. doi:10.1007/s11095-009-0045-6
  11. D'Hondt M, Bracke N, Taevernier L, Gevaert B, Verbeke F, Wynendaele E, et al. Related impurities in peptide medicines. Journal of Pharmaceutical and Biomedical Analysis 2014;101:2–30. doi:10.1016/j.jpba.2014.06.012

See also

Cite this page

Text

Cosmic Peptides. (2026, October 25). Sermorelin and CJC-1295 (no DAC) compared. Cosmic Peptides Research Library. Retrieved October 26, 2026, from https://cosmicpeptides.com/research/peptides/compare/sermorelin-vs-cjc-1295-no-dac

BibTeX

@misc{cosmicpeptides_research_peptides_compare_sermorelin_vs_cjc_1295_no_dac,
  author       = {{Cosmic Peptides}},
  title        = {Sermorelin and CJC-1295 (no DAC) compared},
  howpublished = {Cosmic Peptides Research Library},
  year         = {2026},
  month        = oct,
  url          = {https://cosmicpeptides.com/research/peptides/compare/sermorelin-vs-cjc-1295-no-dac},
  urldate      = {2026-10-26},
  note         = {Last reviewed 2026-10-25}
}

RIS

TY  - ELEC
AU  - Cosmic Peptides
TI  - Sermorelin and CJC-1295 (no DAC) compared
T2  - Cosmic Peptides Research Library
PB  - Cosmic Peptides
PY  - 2026
DA  - 2026/10/25
UR  - https://cosmicpeptides.com/research/peptides/compare/sermorelin-vs-cjc-1295-no-dac
Y2  - 2026/10/26
LA  - en
ER  - 

Cite the date the page was last reviewed, October 25, 2026, as its version. Reference managers such as Zotero can save this page directly.

Changes to this page

  1. Published Structural comparisons of related peptides

    Eight pairs of related peptides side by side: the sequences aligned, calculated properties, and how mass spectrometry and HPLC tell them apart.

Changes of substance are listed here; wording changes are not. Every correction is also on the corrections log.

For in vitro laboratory research only. Not for human or veterinary use. This library describes chemistry, analytical methods and published laboratory research; it gives no guidance on use in people or animals.