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Molecular Weight
Purity
Storage
Appearance
Solubility
01
DSIP (delta sleep-inducing peptide) is a nine-residue peptide, Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu. It was first isolated in the 1970s from the cerebral venous blood of rabbits during induced sleep, and was named for its reported effect on slow-wave (delta) sleep in early animal experiments.
Despite decades of study, no specific receptor or precursor gene for DSIP has been firmly identified, and its physiological role remains debated. It is supplied as a lyophilized reference material for in vitro research and analytical work.
02
DSIP is a short, flexible, acidic peptide.
Trp1
The only aromatic residue, giving DSIP UV absorbance at 280 nm and natural fluorescence. It is also the main oxidation-sensitive site.
Gly-rich core
Three glycines (Gly3, Gly4, Gly8) make the backbone very flexible; DSIP has no stable folded structure in water.
Acidic residues
Asp5 and Glu9, plus the free C-terminus, give a net negative charge at neutral pH.
Asp5-Ala6
Aspartate followed by a small residue can slowly form an aspartimide and isomerise to isoaspartate, particularly in the mildly acidic range (around pH 4–6).
03
DSIP research spans several decades, with mixed and sometimes conflicting results.
Sleep studies
Early animal studies reported effects on slow-wave sleep; later work has produced inconsistent findings, and the effect remains debated.
Neuroendocrine and stress studies
Research has examined effects on stress-related hormones and on responses to stress in animal models.
Mechanism
No dedicated receptor has been confirmed. DSIP-like immunoreactivity has been reported in several tissues, and related sequences have been studied, but its origin and target remain uncertain.
These findings are cited as research context only; no effects are claimed for this material.
04
Neuropeptide reference
A historical reference compound in neuropeptide and sleep-research methods.
Fluorescence-based methods
Its single tryptophan allows fluorimetric detection and quantification.
Degradation studies
A model for aspartimide/isoaspartate formation at Asp5 and for tryptophan oxidation.
Analytical reference
A small, acidic, glycine-rich peptide for testing HPLC and LC-MS methods.
05
Storage
Store the lyophilized powder at −20 °C, sealed, desiccated and protected from light.
Light and oxidation
Trp1 can photo-oxidise. Use amber vials and handle under subdued light.
Aspartate chemistry
Asp5 can isomerise via an aspartimide, fastest in the mildly acidic range (around pH 4–6) and at higher temperatures. Use solutions promptly and keep them cold.
Reconstitution
Soluble in water and aqueous buffers.
Solutions
Freeze single-use aliquots and avoid repeated freeze–thaw cycles; use low-binding tubes.
06
DSIP is straightforward to separate but needs attention to Trp1 and Asp5.
HPLC
Reversed-phase C18 with a TFA gradient; retention is relatively low because of its polarity. Detect at 214 nm, or at 280 nm for tryptophan-selective detection.
Mass spectrometry
Positive-mode ESI shows [M+H]⁺ at m/z 849.3 and [M+2H]²⁺ at m/z 425.2 (monoisotopic); negative mode also works well because of its acidic residues.
Impurity profile
Typical checks include tryptophan oxidation products (+4, +16, +32 Da), isoAsp5 variants (same mass, different retention), truncated sequences and counter-ion content.
07
Delta sleep-inducing peptide, a nine-residue peptide (Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu) first isolated in the 1970s from rabbit cerebral venous blood during sleep.
No specific receptor or precursor gene has been firmly established, which is one reason its physiological role is still debated.
Trp1, which can oxidise, especially under light, and Asp5, which can isomerise to isoaspartate via an aspartimide, fastest at mildly acidic pH.
Yes. Its single tryptophan fluoresces with excitation near 280 nm and emission near 350 nm, allowing sensitive detection.
[M+H]⁺ at m/z 849.3 and [M+2H]²⁺ at m/z 425.2 (monoisotopic). Its acidic residues also make negative-mode ESI effective.
No. It is supplied strictly as a reference compound for laboratory and analytical research and is not for human or animal use.
DSIP Research Reference. (2026). Pure Peptides Labs Research Catalogue. Retrieved from https://purepeptideslabs.net/research-catalogue/neurochemical-research-peptides/dsip/
Materials listed on this platform are supported by independent testing and published documentation for laboratory research contexts.
