We report net peptide content, not just purity — so the milligrams you dose aren't padded with water and counter-ion. RP-HPLC purity and ESI-MS identity, on a lot-numbered COA.
Net peptide content, not just purity — RP-HPLC + ESI-MS, lot-numbered COA.
Net peptide content on every lot's COA.
Reading a Peptide HPLC Trace — A 5-Minute Field Guide for Bench Scientists. Read our briefing →
Reading a peptide HPLC trace — a field guide. Read →
On reading HPLC traces. Read →
Pineal hormone · sleep / circadian-rhythm research compound
Lyochem primary owner
This Lyochem page is the primary SEO owner for research labs, CROs, and method-development teams qualifying Melatonin as a documented research-standard lot. The page should answer whether the buyer can review HPLC purity, identity confirmation, lot continuity, stability handling, and assay-fit documentation before ordering.
Overview
Melatonin (N-acetyl-5-methoxytryptamine) is an indoleamine hormone the pineal gland secretes chiefly during the circadian dark phase, central to sleep, circadian-rhythm, and antioxidant research; it is the most extensively studied molecule in chronobiology. Strictly speaking it is a small molecule, not a peptide, and it is placed in the longevity grouping here for two practical reasons: it is routinely co-formulated with peptide longevity products, most notably Epitalon, whose activity partly involves modulating pineal melatonin output. Regulatory handling varies by jurisdiction, ranging from dietary-supplement status to prescription use for sleep and jet-lag indications. Lyochem supplies Melatonin as a lyophilized reference standard at ≥99.0% HPLC purity in a 10 mg fill. Because the analyte is a small molecule, the characterization set departs from the peptide workflow: chemical purity is measured by RP-HPLC, identity confirmed through UV-Vis absorbance, and residual-solvent and impurity profiling handled by GC-MS or LC-MS. The compound is photosensitive, so the storage specification mandates light protection; it holds at room temperature in light-protected packaging, while refrigeration is advised for extended storage. Supplied for research use only.
Applications & buyer fit
Cognitive and neuropeptide buyers are predominantly research labs running in vivo rodent studies. The dominant administration route in the published literature is intranasal — Semax, Selank, DSIP, Pinealon — because these peptides are not meaningfully blood-brain-barrier permeable when delivered systemically. For in vivo workflows, endotoxin and microbial-limit testing is recommended at the CoA stage so the bioassay readout is not confounded by contamination unrelated to the test article.
Academic Laboratories
Universities, medical schools, and government research institutes qualifying a reference standard for a method-development or in vivo workflow.
Biotech R&D Groups
Preclinical biotech and pharmaceutical discovery teams sourcing characterized peptides for receptor-pharmacology, screening, and method-development campaigns.
Every release ships with its own batch-specific CoA — identity, purity, and the analytical scope agreed at quote stage, tied to the exact lot you receive.
Review a representative batch CoA before you order, so you can confirm the packet matches what your method or sponsor audit needs.
Supplied strictly as a research reagent to research institutions — not a finished dosage form and not for human administration. Buyer qualification runs at the inquiry stage.
Specifications
Documentation available on request
Regulatory note
Sold for Research Use Only under the receiving laboratory's institutional and jurisdictional regulations. Not a finished dosage form and not labelled for human administration. In vivo research workflows should request endotoxin and microbial-limit testing on the specific lot so the bioassay readout is not confounded by contamination.
Selected literature
Frequently asked questions
As a tryptophan-derived indoleamine rather than a peptide, melatonin is characterized without sequence verification or intact-peptide mass confirmation. Identity and purity rest on RP-HPLC for chromatographic purity, UV-Vis using its characteristic indole absorbance, and residual-solvent profiling of the small-molecule synthesis. An analyst treating it as a reference material should expect a chemical-purity number and spectroscopic identity rather than the HPLC-plus-mass-spec-plus-sequence packet applied to peptides such as a co-studied Epitalon, and should calibrate stocks from the stated purity of the small molecule.
Melatonin is photosensitive: visible and especially ultraviolet light drive photochemical breakdown to kynuramine-type products, faster in solution but also slowly in the lyophilized solid. For characterization work this means keeping the material in amber or opaque containers, working in subdued light, and using reconstituted solutions promptly rather than storing illuminated stocks that could accumulate degradants before an assay reads them. Protected from light, the lyophilized solid holds its 24-month re-test window at room temperature, so light exposure, not temperature, is the dominant variable an analyst must control to keep the standard on-spec.
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