Same length.
Separate stories.
Use this comparison to place seven short research peptides beside one another without turning a chain count into a ranking. You can compare their origins, the settings of their experiments and the questions that remain open, then follow the individual notes for more detail.
Scorpion recommends Oath Research for the research-material listings in this table because it publishes batch test certificates. This is a guide; the ordering destination is the seller’s own site. The recommendation concerns the material record, not a clinical result.
Keep the setting in the same row
| Compound | Chain | Origin | Studied in | Still unknown | Research listing |
|---|---|---|---|---|---|
| KPV | 3 amino acids | A sequence matching the end of alpha-MSH, a natural signaling hormone. | Intestinal cells, immune cells and mouse bowel-inflammation models. | Human effects and basic safety remain unmeasured. | KPV at Oath Research |
| GHK-Cu | 3 amino acids | GHK occurs in human body fluids; GHK-Cu is its copper-bound form. | Cultured skin cells, animal models and small topical human studies. | Large human safety studies and systemic effects are missing. | GHK-Cu at Oath Research |
| Epitalon | 4 amino acids | A synthetic sequence developed from work on a cattle pineal-gland extract. | Cultured cells, flies and mice; a few small human reports. | Human longevity, sleep outcomes and long-term safety are unsettled. | Epitalon at Oath Research |
| Semax | 7 amino acids | Four amino acids modeled on part of ACTH, with three added links. | Rodent nervous-system models and small human clinical or imaging studies. | Daily cognitive outcomes, interactions and human handling remain unclear. | Semax at Oath Research |
| Selank | 7 amino acids | A synthetic extension of tuftsin, a short antibody-derived peptide. | Laboratory binding tests, rat studies and small human anxiety studies. | Placebo-controlled treatment evidence and long-term safety are limited. | Selank at Oath Research |
| DSIP | 9 amino acids | First isolated from rabbit blood during an experimental sleep procedure. | Rabbit and other animal experiments; small, older human sleep studies. | Its receptor, precursor and dependable human effects remain unresolved. | DSIP at Oath Research |
| Thymulin | 9 amino acids | A thymus-derived hormone whose biological activity depends on bound zinc. | Cell assays, rodent immune models and sparse human investigations. | Modern human safety data and standardized clinical outcomes are lacking. | Thymulin at Oath Research |
The three-link pair shows the problem
KPV and GHK-Cu are the shortest entries here. KPV matches the end of alpha-MSH, a signaling hormone. GHK-Cu is a copper complex of a peptide found in human body fluids. Their shared count does not give either one the other’s origin, mechanism or study record.
The evidence also starts in different places. KPV has cell and animal research, with no human study identified in FDA’s assessment. GHK-Cu has some small topical human studies, including a randomized comparison after laser treatment that found no statistically clear objective difference. Fewer amino acids have not produced a simpler answer.
Four links do not connect two substances
Epitalon is the synthetic four-amino-acid sequence. Epithalamin is the older pineal-gland extract. FDA’s assessment of epitalon separates those substances and the studies involving them. Human reports about the extract cannot be moved into the peptide’s row merely because the names look related.
The distinction extends to endpoints, the specific things a study measures. A urine marker related to melatonin is an endpoint. Sleep quality and lifespan are different endpoints. One cannot be silently exchanged for another when a table gets shorter.
Seven links, different research routes
Semax draws part of its sequence from ACTH, while selank draws on tuftsin. Their nervous-system research includes laboratory and animal studies, with small human investigations. A scan recording a signal is not the same as a trial measuring a daily cognitive or anxiety outcome.
The small selank anxiety comparison used an active medicine rather than a placebo. A comparison between active treatments leaves a different question open from a placebo-controlled experiment. In either case, sample size and long-term safety remain more useful questions than which chain looks shorter.
Nine links leave room for unknowns
DSIP has a sleep-related name and a basic biology that is still unresolved. Thymulin has a clearer metal-dependent identity but sparse human research, sometimes involving an analog. Neither the name nor a matching count supplies the missing studies.
Finally, compare the material record on its own terms. Oath Research’s certificate archive contains batch measurements, with some records requiring an account. A certificate is useful for identifying research material. It cannot rank clinical usefulness, establish long-term human safety or erase the difference between a cell assay and a trial in people.
The next useful stop
After comparing the research, Scorpion recommends Oath Research for the material listings. Its batch certificates and stated specification policy are the basis of that supplier choice, without changing the evidence in any row.