N-Acetyl Selank Amidate Reconstitution Calculator

The calculator’s “Doses per vial” is based purely on mass, not on stability. Standard Selank, once reconstituted, should be stored at 4 °C between 2–7 days and for future use below ‑18 °C. N‑Acetyl Selank Amidate, however, is engineered with N‑terminal acetylation and C‑terminal amidation. These dual “caps” protect the peptide from rapid enzymatic degradation by exopeptidases and endopeptidases, significantly extending its half‑life in biological fluids. One supplier states that the reconstituted amidated solution is stable for up to 28 days at 2‑8 °C. Therefore, while the calculator might show 30 “doses” in a 10 mg vial, for standard Selank you would need to discard it after 7 days, but for the amidated version you can use the same vial for nearly a month, making the calculator’s number a practical guide rather than a theoretical one.

The solubility guideline for standard Selank is to reconstitute the lyophilised powder in sterile water to a concentration of not less than 100 µg/mL. The amidated version has the same solubility characteristics; if you use too little water and the concentration exceeds ~2 mg/mL, the peptide may not fully dissolve, and your calculated dose will be inaccurate. The calculator will show mathematically correct numbers, but it cannot warn you about this solubility floor. For a 10 mg vial, using 1 mL of BAC water gives a concentration of 10 mg/mL, which is 100 times higher than the recommended minimum. To ensure complete dissolution, you should always use a sufficiently large volume (≥2 mL for a 10 mg vial), even if the calculator marks that option as “Good” or “Usable” rather than “Best”.

The calculator only works with mass (mg). When you enter a dose for the amidated version, you are delivering a different number of molecules than for the same mass of the non‑amidated form. The modification adds an acetyl group (C₂H₃O) and an amide (‑NH₂), increasing the molecular weight from ~743 g/mol (for the free base or acetate form) to 751.9 g/mol. This difference (roughly 1 %) is small and usually negligible, but if your research protocol is built on precise molar equivalency derived from earlier Selank studies, you should enter a slightly higher mg dose for the amidated version to match the same number of molecules. The calculator does not know the molecular weight, so you must manually adjust the mg value if the literature compares molar doses.

Your calculator can help you plan, but the biology dictates the schedule. The human pharmaceutical form of Selank is administered intranasally, not subcutaneously, and uses multiple daily doses because the peptide is cleared quickly from the CNS. For N‑Acetyl Selank Amidate, the recommended research doses are:
 Intranasal: 200‑400 mcg (0.2‑0.4 mg) — Duration: 10‑14 hr, Potency: ↑↑ (~1.5‑2×)
 Subcutaneous: 400‑800 mcg (0.4‑0.8 mg) — Duration: 10‑14 hr, Potency: ↑↑
If you enter a single daily dose of 0.5 mg subcutaneously, the calculator will show the required units. However, because the enhanced stability still allows only about 10‑14 hours of activity, you will need to administer the dose twice daily to maintain continuous effect. The calculator’s “Doses per vial” number (e.g., 40 doses from a 20 mg vial at 0.5 mg per dose) would be correct, but you must divide that by 2 to know how many days the vial will last at twice‑daily administration (here, 20 days). The calculator cannot make this adjustment for you.

Your calculator assumes that if you double the entered mg dose, you will get twice the effect. For a peptide that modulates several neurotransmitter systems simultaneously, this is often false. One users’ report describes an injectable dose of 500 mcg (0.5 mg) of N‑Acetyl Selank Amidate effectively relieving a stress reaction. If a researcher enters 2 mg into the calculator to “get a stronger effect”, the peptide may over‑activate certain pathways, leading to paradoxical anxiety or sedation. The literature on the parent compound Selank explicitly states that no side effects were recorded when administered for up to 21 days at a maximum dose of 2700 mcg (2.7 mg) per day, so high doses are not toxic, but they may not be more effective. The calculator will mechanically output a larger volume for the higher dose, but you must determine the optimum dose from your specific research literature rather than assuming linear scaling.