Description
PrymaLab · Research Use Only
DSIP 10mg
Delta sleep-inducing peptide · extended-supply vial · nonapeptide
DSIP 10mg peptide is an extended-supply lyophilized vial of delta sleep-inducing peptide, CAS 62568-57-4, molecular weight 848.82. Ten milligrams is approximately 11.78 micromoles, twice the standard fill, which suits the replication-focused work this compound most requires.
Specification Table
| Property | Value |
|---|---|
| Compound | Delta sleep-inducing peptide |
| Vial content | 10 mg lyophilized powder |
| Molar content of vial | Approximately 11.78 µmol |
| Stock at 2 ml diluent | Approximately 5.89 mM |
| Common designation | DSIP |
| Alternative name | Emideltide |
| CAS number | 62568-57-4 |
| Molecular formula | C35H48N10O15 |
| Molecular weight | 848.82 g/mol |
| Residue count | 9 |
| Single-letter sequence | WAGGDASGE |
| Three-letter sequence | Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu |
| Net charge at neutral pH | Negative, from two acidic residues |
| Year first described | 1977 |
| Originating group | Schoenenberger and Monnier, University of Basel |
| Source of the original isolate | Cerebral venous blood of rabbits under electrical thalamic stimulation |
| Receptor | Not identified. No specific receptor has been characterised |
| Oxidation-prone residues | Tryptophan at position 1 |
| Deamidation-prone motifs | None. No Asn-Gly present |
| Appearance | White lyophilized powder |
| Purity | Per lot-specific certificate of analysis |
| Solubility | Water soluble |
| Storage, lyophilized | -20°C, protected from light and moisture |
| Storage, reconstituted | 2-8°C, protected from light |
| Regulatory status | No approved human or veterinary formulation in any jurisdiction |
What Analytical Confirmation Suits a Nine-Residue Peptide?
Short peptides are easier to characterise than long ones, and DSIP has features that make several checks quick and informative.
Mass spectrometry confirms 848.82. At nine residues the mass is low enough that resolution is excellent on any modern instrument, and deletion sequences differing by one residue are well separated rather than overlapping as they do at greater length.
The tryptophan at position 1 gives a plus-16 satellite when oxidised, and with only one oxidisable residue in the molecule the interpretation is unambiguous. A larger satellite than expected points to storage or synthesis handling rather than to a complex mixture of modification sites.
Absorbance at 280 nm quantifies concentration through that same tryptophan. One tryptophan per molecule makes the calculation direct, and the extinction coefficient for tryptophan is well established.
Reversed-phase chromatography establishes purity. A nine-residue peptide with a single aromatic residue and two acidic residues has a distinctive retention profile, and the acidic residues make the separation sensitive to mobile phase pH, which is worth controlling deliberately.
Why Is This Peptide Chemically Forgiving?
Reviewing what is absent from the sequence explains why DSIP tolerates handling that would degrade other compounds in this catalogue.
No cysteine, therefore no disulfide bonds to form, scramble or reduce. Peptides such as BPC-157 analogues and the various cyclic constructs require attention to redox conditions that simply does not apply here.
No asparagine followed by glycine, the motif responsible for the fastest deamidation route in peptides. Aspartate at position 5 is already in the acid form, so the isoaspartate rearrangement pathway that troubles asparagine-containing sequences is not available.
No methionine, which removes the most common oxidation site. Only the single tryptophan remains, and while tryptophan does oxidise, it does so more slowly than methionine under typical storage conditions.
Small residues dominate the sequence, with four glycines and alanines out of nine. That means no bulky hydrophobic surface driving aggregation, which is a real problem for longer amphipathic peptides and not one here.
The practical upshot is that a DSIP preparation stored reasonably will still be a DSIP preparation, which cannot be said of everything in this catalogue.
What Does the State of the Literature Imply for Design?
A field with an unresolved central question calls for different work than a field with a settled mechanism, and DSIP is firmly in the former category.
The most recent substantive review dates from 2006, and the volume of primary work has declined considerably since the 1980s. That decline is informative: it usually indicates that a line of investigation stopped producing tractable questions rather than that it was resolved.
For a researcher, the implication is that replication carries more value than extension. Reproducing a specific reported observation, with modern methods and adequate controls, addresses the field more usefully than adding a new endpoint to an unreplicated foundation.
A larger vial supports that kind of work directly. Replication requires sufficient material for adequate group sizes and for the concentration ranges that older single-concentration studies did not explore.
Publishing a negative replication is also valuable here, and arguably more so than a positive one, given how much of the existing record derives from a small number of laboratories working decades ago.
How Should DSIP 10mg Peptide Be Divided?
Reconstitute once, aliquot, freeze, thaw each aliquot once. The standard sequence applies and this peptide tolerates it well.
Ten milligrams into 2 ml gives approximately 5.89 mM, matching what a 5mg vial in 1 ml produces, so dilution arithmetic transfers between formats without adjustment.
Aliquot size should match single-experiment consumption. This peptide tolerates freeze-thaw better than most, so the penalty for slightly oversized aliquots is lower than it would be for an oxidation-prone or aggregation-prone sequence.
Standard consumables are adequate. The net negative charge from two acidic residues reduces adsorption to the negatively charged surfaces of ordinary plasticware, unlike the basic peptides in this catalogue which need low-binding tubes at working concentrations.
What Would a Modern Replication Look Like?
Reproducing 1970s and 1980s peptide work with contemporary methods raises specific practical questions that are worth thinking through before committing material.
Peptide identity is the first. The original work used material synthesised and characterised by the methods of its era, and a modern preparation confirmed by high-resolution mass spectrometry and well-resolved chromatography is a better-defined substance than what was originally tested.
That is an advantage for reproducibility and a complication for comparison. If a modern replication fails, one candidate explanation is that the original material contained something the modern preparation does not.
Purity of the original is generally unrecoverable from the published record, since certificates were not routinely reported. A replication should therefore report its own material characterisation in full, so that a future comparison has something to work against.
Readouts have changed substantially. Electroencephalographic analysis, behavioural scoring and biochemical measurement have all advanced, and a modern study will measure more precisely than the original could, which can produce apparent discrepancies that are methodological rather than substantive.
Pre-registering the replication design addresses the interpretive problem that arises when a decades-old finding does not reproduce, by fixing the analysis before the data exist.
How Should Absence of a Receptor Shape the Readouts Chosen?
Without a target, the usual hierarchy of evidence inverts and the choice of readout becomes the main design decision.
Target engagement assays are unavailable, since there is no known target to engage, and binding measurements, occupancy calculations and competitive displacement all require a receptor and none can be performed.
That leaves phenotypic readouts as the only option, which places the entire interpretive burden on controls. A scrambled-sequence arm, a degraded-peptide arm and a full concentration range together carry weight that a binding assay would otherwise carry alone.
Unbiased readouts are more informative than targeted ones in this situation. Transcriptomics or proteomics can reveal what the peptide affects without presupposing a mechanism, whereas a targeted panel can only find what its designer expected.
A negative unbiased finding is also substantive here. Demonstrating that a peptide produces no detectable transcriptional change at a range of concentrations constrains the space of possible mechanisms usefully.
Material at this scale supports that kind of work, which needs replicates and concentration arms rather than a single treated sample.
Why Does DSIP 10mg Peptide Suit Replication Work?
Replication has material requirements that novel work does not, and they push toward the larger fill.
A replication needs adequate statistical power, which means larger group sizes than an exploratory study would use, and it needs those groups run under conditions matched to the original as closely as the published methods allow.
It also needs the controls the original may have omitted. Adding a scrambled-sequence arm and a full concentration range to a design that originally used a single concentration multiplies material consumption several times over.
Running the whole replication from one lot of DSIP 10mg peptide removes material variation as a candidate explanation for any discrepancy, which is exactly the ambiguity a replication is trying to avoid.
Pre-registering the design before the vial is ever opened is the complementary step, and it costs nothing beyond an hour of thought.
Reconstitution and Storage in Laboratory Practice
Two millilitres gives approximately 5.89 mM and keeps calculations consistent with the smaller format.
Dissolution is quick. Add diluent slowly against the vial wall and swirl gently. Material that resists dissolving is worth questioning rather than agitating.
Protect from light throughout on account of the tryptophan, and minimise time with the vial open. These are the only two handling precautions this peptide genuinely requires.
Hold lyophilized material at -20°C sealed and dry, and keep reconstituted solution at 2-8°C in the dark, aliquoted before freezing. Record lot, diluent, volume, concentration and date. With ten milligrams likely to span multiple studies, lot traceability is the record that matters most.
A final point concerns how to report a replication that partly succeeds. Partial reproduction is the common endpoint and it is the hardest to write up honestly.
The useful practice is to state which specific observations reproduced, which did not, and at what effect size, rather than summarising the whole as confirmed or refuted. A study that reproduces one of four reported findings has said something precise, and compressing that into a verdict discards it.
For a compound with an evidence base as thin as this one, that precision matters more than usual.
One last note on nomenclature applies here as it does to the smaller fill. Confirm the sequence rather than the name when ordering, since three designations circulate for this one nonapeptide and only the sequence is unambiguous.
Published Literature
References verified against the publisher record. The declining publication rate in this area since the 1980s is discussed in the sections above and is itself worth noting.
- Schoenenberger GA, Monnier M. Proceedings of the National Academy of Sciences. 1977;74(3):1282-1286.
- Graf MV, Kastin AJ. Neuroscience and Biobehavioral Reviews. 1984;8(1):83-93.
- Kovalzon VM, Strekalova TV. Neuroscience and Biobehavioral Reviews. 2006;30(1):1-7.
- Graf MV, Kastin AJ. Peptides. 1986;7(6):1165-1187.
- Iyer KS, McCann SM. Neuroendocrinology. 1987;46(1):93-95.
Frequently Asked Questions
What is DSIP 10mg peptide?
An extended-supply lyophilized vial of delta sleep-inducing peptide, the nonapeptide WAGGDASGE, CAS 62568-57-4, molecular weight 848.82. Ten milligrams is approximately 11.78 micromoles, twice the standard fill. Laboratory research use only.
Why is mass spectrometry straightforward here?
Because at nine residues the mass is low enough that resolution is excellent on any modern instrument. Deletion sequences differing by a single residue separate cleanly rather than overlapping as they tend to at greater peptide length.
What does a plus-16 satellite indicate?
Oxidation at the single tryptophan. With only one oxidisable residue in the whole molecule the interpretation is unambiguous, and a larger satellite than expected points to storage or synthesis handling rather than a complex mixture of modification sites.
How is concentration determined?
By absorbance at 280 nanometres through the single tryptophan. One tryptophan per molecule makes the calculation direct, and the extinction coefficient for tryptophan is well established, so no standard curve is needed.
Why is this peptide chemically forgiving?
Because of what the sequence lacks. There is no cysteine, so no disulfide chemistry is available to go wrong, and no asparagine-glycine motif, so the fastest deamidation route is absent. No methionine either. Small residues dominate, which leaves no hydrophobic surface to drive aggregation.
Does it need low-binding consumables?
Generally not. The net negative charge from two acidic residues reduces adsorption to the negatively charged surfaces of ordinary plasticware, unlike the basic peptides in this catalogue which do need low-binding tubes at working concentrations.
What does the declining publication rate suggest?
That a line of investigation stopped producing tractable questions rather than that it was resolved. The most recent substantive review dates from 2006 and primary work has declined considerably since the 1980s.
What kind of work does the field need?
Replication rather than extension. Reproducing a specific reported observation with modern methods and adequate controls addresses the field more usefully than adding a new endpoint to an unreplicated foundation.
Is a negative replication worth publishing?
Arguably more than a positive one here, given how much of the existing record derives from a small number of laboratories working decades ago. A well-controlled negative finding would meaningfully constrain what remains an open question.
What reconstitution volume keeps calculations consistent?
Two millilitres, giving approximately 5.89 millimolar, which matches what a 5mg vial reconstituted into 1 ml produces. Dilution arithmetic then transfers between the two formats without adjustment.
Compliance Statement
DSIP 10mg peptide is sold exclusively for laboratory research use. It is not a drug, food, or cosmetic product, and it is not a dietary product of any kind. It is not approved by the FDA or any comparable authority for human or veterinary use, and no receptor for this compound has been identified in nearly five decades of published work. This product is not intended to diagnose, treat, cure, or prevent any disease. It must not be given to humans or animals. Purchase is restricted to qualified researchers and institutions operating within applicable laws. All handling is the responsibility of the purchasing laboratory.
19 reviews for DSIP 10MG