DSIP — wholesale 10-vial kits

Research context

DSIP, delta sleep-inducing peptide, is the nonapeptide Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu. It is also indexed under the INN emideltide. The peptide came out of cross-circulation experiments in rabbits run by Marcel Monnier and colleagues in Basel, in which blood from an animal with electrically stimulated sleep-related brain regions produced delta-wave EEG activity in a recipient animal. In 1977 Guido Schoenenberger, Monnier and co-workers reported the isolation and chemical synthesis of the nonapeptide and compared the natural and synthetic material in Experientia, which established the reference sequence still used today. A companion 1977 report in the same journal described transport of the synthetic peptide across the blood–brain barrier in rabbits.

Structurally DSIP is about as simple as a nonapeptide gets, and that simplicity is why it remains a useful model compound. It is unmodified, linear and disulfide-free; two glycine pairs give it a flexible backbone with little secondary structure in solution; aspartate and glutamate make it acidic and highly water-soluble; and the single N-terminal tryptophan is the only chromophore, giving strong absorbance near 280 nm. Phosphorylation of the serine residue has been described in the older literature as a naturally occurring variant, which is one reason mass-spectrometric identity confirmation matters when comparing material between studies.

Decades later DSIP is still an unresolved case. No dedicated gene, precursor or receptor has been confirmed, and the sleep-related findings from the founding experiments were not reproduced consistently between laboratories — a 2006 review in the Journal of Neurochemistry surveys the record under the title of a still-unresolved riddle. Research has broadened to interactions with stress-hormone axes, opioid and glutamatergic signaling, and antioxidant chemistry, all at a proposed-mechanism level.

For a laboratory, the molecule is used mainly as a reference peptide rather than a probe of a known target: a model substrate in peptide-transport and blood–brain-barrier permeability work, a test analyte in degradation-kinetics and peptidase-mapping experiments, an EEG-pharmacology comparator in animal models, and an identity and quantitation standard for LC-MS and immunoassay methods. Its tryptophan absorbance makes it a straightforward concentration control for plate-reader and spectrophotometer calibration in short-peptide work, and its acidic, flexible sequence is a common negative control in experiments where receptor-mediated activity is the thing being tested.

Regulatory position, stated factually: DSIP is not FDA-approved and is not the active ingredient of any approved product. FDA lists emideltide (DSIP) among bulk drug substances whose compounding nominations were withdrawn by the nominators; emideltide-related bulk substances were discussed at the Pharmacy Compounding Advisory Committee meeting of July 23–24, 2026, and DSIP was not among the peptide substances covered by the October 2026 HHS interim enforcement-discretion notice. WholesalePeptide.us supplies DSIP as a research reference standard for in-vitro, analytical and preclinical laboratory research.

The N-terminal tryptophan gives DSIP strong UV absorbance at 280 nm, useful for concentration checks alongside the RP-HPLC purity reported on each lot's COA.

Research areas

• slow-wave sleep EEG in animal models
• neuropeptide transport across the blood–brain barrier
• HPA-axis and stress-hormone signaling
• peptide degradation kinetics
• EEG pharmacology in animal models
• reference-standard use in LC-MS method development

U.S. regulatory status of the compound (as an active ingredient): Not approved by the FDA. The material sold here is a research reference chemical, not a drug product.

Handling and storage

• Store lyophilized vials at −20 °C, sealed, protected from light and moisture.
• Let the vial equilibrate to room temperature before opening to limit condensation.
• Reconstitute in an appropriate sterile buffer or solvent according to your laboratory SOP.
• Aliquot reconstituted material and avoid repeated freeze–thaw.