# Melatonin (Research Grade)

> Research-grade N-acetyl-5-methoxytryptamine in 10 mg and 50 mg vials

All products are sold strictly for laboratory research use only. Not for human or veterinary use.

- Web page: https://peptidemedixeu.com/en/products/melatonin/
- Brand: Peptide Medix EU
- Category: [Sleep & Stress Peptides](https://peptidemedixeu.com/en/collections/sleep-peptides/)
- Purity: ≥99% by HPLC; lot-matched COA available
- CAS number: 73-31-4
- from €34 (EUR)

## Sizes and prices (EUR)

| Size | Price | SKU |
| --- | --- | --- |
| 10 mg | €34 | MELATONIN-10-MG |
| 50 mg | €68 | MELATONIN-50-MG |

_Catalog prices at build time; the web page and checkout are authoritative._

## Specifications

- **CAS number:** 73-31-4
- **Molecular formula:** C13H16N2O2
- **Molecular weight:** 232.28 g/mol
- **Form:** Crystalline powder in a sealed glass vial
- **Purity:** ≥99% by HPLC; lot-matched COA available
- **Available sizes:** 10 mg, 50 mg
- **Solubility:** Sparingly soluble in water; readily soluble in ethanol or DMSO for stock preparation
- **Chemical name:** N-acetyl-5-methoxytryptamine
- **Compound class:** Indoleamine; tryptophan-derived pineal hormone (small molecule, not a peptide)
- **Biosynthetic origin:** Tryptophan to serotonin to N-acetylserotonin to melatonin, via AANAT and ASMT
- **Molecular targets studied:** MT1 and MT2 G-protein-coupled receptors; quinone reductase 2 (MT3 site)
- **Research areas:** Circadian rhythm and chronobiology, sleep-onset physiology, oxidative stress, mitochondrial function, seasonal and reproductive biology
- **Storage (powder):** −20 °C, sealed, desiccated and protected from light
- **Storage (in solution):** 2–8 °C in amber or foil-wrapped vessels; aliquot frozen stocks

## Description

Melatonin (N-acetyl-5-methoxytryptamine) is an indoleamine that the pineal gland makes from tryptophan via serotonin; arylalkylamine N-acetyltransferase and acetylserotonin O-methyltransferase catalyse the last two steps. The suprachiasmatic nucleus controls its production, and light hitting the retina shuts it off — which is why blood levels climb after nightfall and drop sharply at dawn. This close link to the light–dark cycle has made melatonin a standard reference compound in chronobiology.

What we sell here is the small molecule itself, not a peptide: research-grade powder in sealed vials of 10 mg or 50 mg. Melatonin signals through two Gi-coupled receptors, MT1 and MT2, which lower cyclic AMP, and it also binds quinone reductase 2 (once called MT3). Separately from any receptor, its indole ring directly scavenges reactive oxygen and nitrogen species, so the literature falls neatly into receptor-based chronobiology on one side and redox studies on the other.

## Frequently asked questions

### Should melatonin be classed as a peptide?

No. It is a small tryptophan-derived indoleamine of roughly 232 g/mol — about a tenth the size of a typical research peptide. We list it with sleep-related peptides such as DSIP because their research areas overlap, not because the structures are related.

### Which vial sizes and what purity?

10 mg and 50 mg vials of research-grade powder, HPLC-tested to ≥99%. A certificate covering purity and identity accompanies each lot; quote the lot number on your vial when asking for it.

### What's the best way to dissolve it?

It dissolves only sparingly in water. Standard practice is a concentrated ethanol or DMSO stock diluted into aqueous buffer shortly before use, keeping the final solvent level low enough not to disturb the assay. Confirm solubility in your particular buffer.

### Why keep it in the dark?

Its indole ring is light-sensitive and measurably degrades under ordinary lab lighting, and solutions oxidise faster than dry powder. Store it sealed, cold and dark, use amber or foil-wrapped vessels for solutions, and log light exposure where quantitative precision matters.

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All products offered on this website are intended solely for in-vitro laboratory research and development by qualified professionals. They are not drugs, foods, cosmetics or dietary supplements, and are not intended to diagnose, treat, cure or prevent any disease. Products must not be introduced into humans or animals in any manner. By purchasing, you confirm that you are a qualified researcher and accept full responsibility for handling and storage in accordance with applicable laws.

Peptide Medix EU · https://peptidemedixeu.com/en/products/melatonin/