The N-acetylated derivative of Selank (parent: TKPRPGP, the Russian Academy of Sciences anxiolytic). Zero PubMed-indexed primary literature on the N-acetylated form itself. Every "stronger / longer-acting" claim is medicinal-chemistry intuition plus parent-Selank pharmacology imported wholesale.
N-Acetyl Selank (also written NA-Selank, Ac-Selank) is the N-terminally acetylated derivative of Selank, with sequence Ac-Thr-Lys-Pro-Arg-Pro-Gly-Pro (Ac-TKPRPGP). The acetyl group caps the N-terminus to reduce aminopeptidase cleavage.
Parent Selank is Thr-Lys-Pro-Arg-Pro-Gly-Pro (TKPRPGP), where TKPR is the immune-modulating tetrapeptide tuftsin and PGP is a proline-glycine-proline cap (the same C-terminal motif used in Semax for protease resistance). Selank originated at the Russian Academy of Sciences Institute of Molecular Genetics (Moscow) in the 1990s — same lab pedigree as Semax — and is registered in Russia as a nasal solution drug for anxiety / asthenia.
The audit-critical asymmetry: parent Selank has substantial Russian primary literature, but N-Acetyl Selank has zero PubMed-indexed primary literature on the N-acetylated molecule itself. Direct searches for "N-acetyl selank," "NA-Selank," "acetyl-selank," and "Ac-TKPRPGP" all return zero records (verified 2026-05-07). NLM Supplementary Concept lookups return parent Selank only. Every published paper mentioning Selank pharmacology is on the unmodified parent — not on the N-acetylated derivative. Vendor and community claims of "stronger" or "longer-acting" rest on medicinal-chemistry intuition (N-terminal acetylation typically reduces aminopeptidase cleavage) plus wholesale import of parent Selank pharmacology — not on a measured head-to-head comparison.
Every mechanism claim below is from the parent Selank literature. None has been measured for the N-acetylated derivative itself.
Parent Selank pharmacology: anxiolytic without sedation in head-to-head Russian clinical work — Zozulya 2008 (PMID 18454096) compared vs medazepam in generalized anxiety / neurasthenia (n=62), and Medvedev 2014 (PMID 25176261) compared vs phenazepam with reported 1-week post-dose effect persistence. GABAergic gene expression modulation in rat frontal cortex (Volkova 2016, PMID 26924987). BDNF upregulation in rat hippocampus with intranasal dosing (Inozemtseva 2008, PMID 18841804). Enkephalin-degrading peptidase inhibition (Kost 2001, PMID 11550013, IC50 ~15–20 µM) — may underlie part of the anxiolytic and analgesic profile. Th1/Th2 cytokine shift / IL-6 mRNA suppression in PBMC (Uchakina 2008, PMID 18577961). Anticoagulant-like activity of proline-rich peptides (Bakaeva 2006, PMID 16634437). Negative result worth flagging: Filatova 2017 (PMID 28293190) found no protective effect of Selank alone on IMR-32 cells in vitro.
What the N-acetyl modification is hypothesized to do, by analogy to other N-acetylated peptides: reduced aminopeptidase cleavage at the N-terminus (longer plasma residence); possibly improved BBB penetration via altered hydrophobicity/charge; vendor framing of "stronger and longer-acting Selank." None of this has been measured for N-Acetyl Selank specifically.
| Claim | Source | What it actually measured |
|---|---|---|
| Anxiolytic effect comparable to benzodiazepines | Zozulya 2008 PMID 18454096; Medvedev 2014 PMID 25176261 | Parent Selank only. |
| GABAergic gene expression modulation | Volkova 2016 PMID 26924987 | Parent Selank only. Rat frontal cortex. |
| BDNF upregulation in hippocampus | Inozemtseva 2008 PMID 18841804 | Parent Selank only. Rat, intranasal. |
| Enkephalin-degrading peptidase inhibition | Kost 2001 PMID 11550013 | Parent Selank only. In vitro. |
| Immune cytokine shift (Th2→Th1) | Uchakina 2008 PMID 18577961 | Parent Selank only. |
| "Longer half-life vs Selank" | None | Not measured for N-Acetyl Selank. |
| "Stronger anxiolytic effect" | None | Not measured. |
| Human PK / safety of N-Acetyl Selank | None | No published study. |
If the source is a parent-Selank paper, label it as such — don't silently import it as if it measured the derivative.
Build your protocol, log every dose, monitor your body's response, and get reminders so you never miss a dose.
Start Tracking FreeNo published trial of N-Acetyl Selank exists. The dosing below is community / vendor convention extrapolated from parent Selank protocols.
| Parameter | Common Range |
|---|---|
| Dose (intranasal) | 250–750 µg/spray, 1–3 sprays/day; total ~250–2250 µg/day |
| Dose (SC, less common) | 250–500 µg/day |
| Frequency | Daily, morning preference (community) |
| Cycle length | 2–6 weeks (community); parent Selank trials were similar |
| Route | Intranasal most common; SC less common |
The "longer half-life" framing is sometimes used to justify less-frequent dosing (every-other-day or twice-weekly), but no published PK study supports specific intervals for the N-acetylated form.
For a typical 5 mg lyophilized vial: add 2 mL bacteriostatic water → 2.5 mg/mL. On a U-100 insulin syringe, 1 unit = 25 µg. For a 500 µg intranasal dose, draw 0.2 mL (20 units).
Storage: lyophilized is stable at room temperature short-term, refrigerate longer-term. Reconstituted: refrigerate, use within 28 days. Nasal solution: protect from light; refrigerated. For the full protocol, see the Bacteriostatic Water guide.
Pre-filled with a typical N-Acetyl Selank setup. Edit any field — the draw updates live.
Insulin syringe — 100 units = 1 mL
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No published human safety data on N-Acetyl Selank. No FAERS, EudraVigilance, or Yellow Card entries.
Parent Selank safety profile (extrapolated): generally well-tolerated in Russian clinical trials; mild irritability or insomnia with later-day dosing (community); nasal irritation with intranasal route; transient headache; no abuse potential or withdrawal pattern reported (one of the framings that motivated parent Selank as a benzodiazepine alternative).
Theoretical concerns specific to N-acetylation: if the N-acetyl group really does extend half-life as claimed, accumulation effects with chronic dosing could differ from parent Selank. Not characterized in published research.
| Compound | Difference from N-Acetyl Selank |
|---|---|
| Selank (parent) | Unmodified TKPRPGP. All published evidence is on the parent. Russian-registered drug. N-Acetyl form has no published trials. |
| N-Acetyl Semax | Sister N-acetyl modification on a different parent (MEHFPGP, ACTH(4-7) analog). Same modification logic, different parent, different mechanism. |
| N-Acetyl Semax Amidate | N-Acetyl Semax with C-terminal amidation. Different molecule. |
| Tuftsin | The TKPR tetrapeptide that forms the immune-modulating core of Selank. |
| Semax | Parent ACTH(4-7) analog from the same Russian Academy lab. Different sequence and mechanism (BDNF/NGF nootropic). |
| Cerebrolysin | Porcine brain extract; multi-component; different family. |
| MIF-1 | Different mechanism (D2 PAM); different research lineage. |
Vendor identity confidence: research-chem vendors selling "N-Acetyl Selank" may be supplying Ac-TKPRPGP, parent Selank mislabeled, or other vendor-specific variants. No industry-standard verification — no monograph, no reference standard. Buyer-beware.
N-Acetyl Selank is a research peptide not approved by the FDA for human use. It is sold only as a research chemical, and StackTrax does not endorse or facilitate personal use.
Quality varies enormously among research-chemical suppliers. At minimum, look for:
StackTrax’s preferred partner NextGen Peptides does not currently carry N-Acetyl Selankin their catalog, which is why you don’t see a direct purchase link here. Other major research-chemical suppliers carry it; we don’t specifically recommend one for this compound.
Build your protocol, log every dose, monitor your body's response, and get reminders so you never miss a dose.
Start Tracking FreeN-Acetyl Selank (also written NA-Selank, Ac-Selank) is the N-terminally acetylated derivative of Selank, with sequence Ac-Thr-Lys-Pro-Arg-Pro-Gly-Pro (Ac-TKPRPGP). The acetyl group caps the N-terminus to reduce aminopeptidase cleavage. Parent Selank is TKPRPGP, where TKPR is the immune-modulating tetrapeptide tuftsin and PGP is a proline-glycine-proline cap. Parent Selank originated at the Russian Academy of Sciences Institute of Molecular Genetics in the 1990s and is registered in Russia as a nasal solution for anxiety and asthenia. The N-acetyl form is not registered separately anywhere.
No — and this is the audit-critical asymmetry. Parent Selank has substantial Russian primary literature, but N-Acetyl Selank has zero PubMed-indexed primary literature on the N-acetylated molecule itself. Direct searches for "N-acetyl selank," "NA-Selank," "acetyl-selank," and "Ac-TKPRPGP" all return zero records. Every vendor and community claim of "stronger" or "longer-acting" rests on medicinal-chemistry intuition (N-terminal acetylation typically reduces aminopeptidase cleavage) plus wholesale import of parent Selank pharmacology — not on a measured head-to-head comparison.
Parent Selank has been characterized as a non-sedating anxiolytic in Russian clinical work. Zozulya 2008 (PMID 18454096) compared it head-to-head with medazepam in generalized anxiety and neurasthenia (n=62), and Medvedev 2014 (PMID 25176261) compared it with phenazepam and reported 1-week post-dose effect persistence. Mechanistic work shows GABAergic gene expression modulation in rat frontal cortex (Volkova 2016, PMID 26924987), BDNF upregulation in rat hippocampus with intranasal dosing (Inozemtseva 2008, PMID 18841804), and enkephalin-degrading peptidase inhibition (Kost 2001, PMID 11550013). None of this has been measured for the N-acetylated derivative itself.
FDA: never approved (parent or N-acetyl form). EMA: not approved. Russia: parent Selank is registered as a nasal solution but the N-acetyl derivative is NOT registered separately — the regulatory authorization is for the unmodified parent only. WADA 2026: not on the prohibited list by name, but as an unapproved investigational substance the S0 catch-all may apply. Sold in the US as a research chemical only.
No published trial of N-Acetyl Selank exists. Community/vendor convention, extrapolated from parent Selank protocols, is 250–750 mcg per spray intranasally, 1–3 sprays per day (total roughly 250–2250 mcg per day). Subcutaneous dosing is less common at 250–500 mcg per day. Cycles are typically 2–6 weeks. The "longer half-life" framing is sometimes used to justify less-frequent dosing (every-other-day or twice-weekly), but no published PK study supports specific intervals for the N-acetylated form.
For a typical 5 mg lyophilized vial, add 2 mL bacteriostatic water to yield 2.5 mg/mL (2500 mcg/mL). On a U-100 insulin syringe, 1 unit equals 25 mcg. For a 500 mcg intranasal dose, draw 0.2 mL (20 units). Storage: lyophilized is stable at room temperature short-term, refrigerate longer-term. Reconstituted: refrigerate and use within 28 days.
No published human safety data on N-Acetyl Selank specifically. No FAERS, EudraVigilance, or Yellow Card entries. Parent Selank safety profile (extrapolated): generally well-tolerated in Russian clinical trials, with mild irritability or insomnia at later-day dosing per community reports, nasal irritation with intranasal route, transient headache, and no abuse potential or withdrawal pattern reported. One specific N-acetylation caveat: if the N-acetyl group really does extend half-life as claimed, accumulation effects with chronic dosing could differ from parent Selank — uncharacterized in published research.
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StackTrax guides cover peptides and compounds that are not FDA-approved for the uses discussed. The dosing, reconstitution, and safety information is compiled from published research and community protocols for educational purposes only.
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