Peptide reference · Linear nonapeptide
DSIP COA check: molecular weight, formula and what to look for
Use these reference values to check the identity result on a DSIP Certificate of Analysis. The theoretical average molecular weight of DSIP is 848.81 Da and the monoisotopic mass is 848.330 Da.
Check a DSIP COA nowDSIP reference data
| Name | DSIP |
|---|---|
| Also known as | Delta Sleep-Inducing Peptide |
| Type | Linear nonapeptide |
| Molecular formula | C35H48N10O15 |
| Average molecular weight | 848.81 g/mol (Da) |
| Monoisotopic mass | 848.3301 Da |
| Residues | 9 |
| Sequence | Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu |
| Reference source | PubChem CID 68816 (formula and mass cross-checked) |
Expected mass spectrometry ions
A DSIP COA may list one of these m/z values instead of the neutral mass. That is still consistent with DSIP. How charge states work.
| Ion | m/z (monoisotopic) | m/z (average) |
|---|---|---|
| [M+H]+ | 849.34 | 849.82 |
| [M+2H]2+ | 425.17 | 425.41 |
| [M+3H]3+ | 283.78 | 283.94 |
What else can show up on a DSIP COA
Masses calculated from DSIP's formula and sequence for the adducts, degradation products and synthesis impurities a lab report can show. A match tells you what the extra peak probably is.
| Signal | Value | What it means |
|---|---|---|
| Na adduct, deconvoluted (M + 21.98) | 870.31 Da | Sodium adduct: an MS artifact, not a separate impurity. The [M+Na]+ ion itself is at M + 22.99 |
| K adduct, deconvoluted (M + 37.96) | 886.29 Da | Potassium adduct: an MS artifact. The [M+K]+ ion itself is at M + 38.96 |
| TFA adduct (M + 113.99) | 962.32 Da | Trifluoroacetic acid from purification seen as an adduct; residual TFA salt is real vial content |
| M + 16 (oxidation) | 864.32 Da | Oxidation of Trp |
| M − 18 (aspartimide) | 830.32 Da | Aspartimide formation at Asp |
Deletion sequences (6): one residue missing
| Signal | Value | What it means |
|---|---|---|
| des-Trp (M − 186.08) | 662.25 Da | Deletion sequence missing one Trp |
| des-Ala (M − 71.04) | 777.29 Da | Deletion sequence missing one Ala |
| des-Gly (M − 57.02) | 791.31 Da | Deletion sequence missing one Gly |
| des-Asp (M − 115.03) | 733.30 Da | Deletion sequence missing one Asp |
| des-Ser (M − 87.03) | 761.30 Da | Deletion sequence missing one Ser |
| des-Glu (M − 129.04) | 719.29 Da | Deletion sequence missing one Glu |
Adduct rows are deconvoluted masses (the shift seen against [M+H]+); the singly charged [M+Na]+ ion itself sits at M + 22.99. Deletion masses alone can't say which copy of a repeated residue is missing.
Short peptides like DSIP (9 residues) are easy to make cleanly, so 98% HPLC purity should be the floor, not the goal. The full checklist is in how to read a peptide COA.
DSIP-specific things to watch
DSIP is a nine-residue linear peptide (WAGGDASGE), about 848.8 Da.
It contains an aspartic acid residue, a common site of slow chemical degradation in peptides (for example aspartimide formation and isomerization), so a recent test date and cold, dry storage matter.
Expect [M+H]⁺ near 849.3 m/z. The N-terminal tryptophan gives DSIP a strong UV signal, so HPLC purity readings at 280 nm are also meaningful.
DSIP's N-terminal tryptophan can oxidize (+16 Da, near 864.3 Da monoisotopic), and losing it leaves a 662.3 Da fragment. Because DSIP is acidic, some labs run negative mode, where [M-H]- appears near 847.3 m/z.
Regulatory status differs from its neighbors: in July 2026 an FDA advisory committee vote to add DSIP (emideltide) to the 503A bulks list failed, 6 for and 7 against, and it isn't among the six peptides in the October 2026 HHS compounding policy.
Compounds with similar mass
If a COA's mass is off, compare it with these neighbors. A match to one of them can point to a mislabeled product.
Sources
- PubChem CID 68816: DSIP formula and reference mass.
- CIAAW: Standard atomic weights: Used to calculate average molecular weights.
- NIST CODATA: proton mass: Used to convert m/z charge states to neutral mass.
- PeptideCOACheck methodology: How the checker's thresholds work.
- Peptides at a crossroads (Holland & Knight, Oct 16, 2026): Reports the July 2026 Pharmacy Compounding Advisory Committee votes, including emideltide (DSIP) failing 6-7.
- HHS will permit compounding of six peptides ahead of formal rulemaking (RAPS, Oct 29, 2026): Lists the six peptides in the October 28, 2026 HHS policy.
Last updated . Written and maintained under our editorial policy. Found an error? See corrections.
Frequently asked questions
Is emideltide the same as DSIP?
Yes. Emideltide is the generic name for delta sleep-inducing peptide, WAGGDASGE, about 848.8 Da.
Why does my DSIP COA show 847 instead of 849?
The lab ran negative mode. 847.3 m/z is [M-H]-.
Is DSIP covered by the October 2026 HHS compounding policy?
No. That policy covers six other peptides. A July 2026 FDA advisory committee vote to add DSIP to the 503A bulks list failed.
For laboratory research use only. This page describes analytical chemistry data. It is not medical advice and makes no claim about effects in humans or animals.