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Research peptide glossary: the terms on supplier pages and certificates

Updated 14 Oct 20262 min read

In short

Purity (HPLC) is a ratio; net content is an amount; identity (mass spectrometry) confirms the molecule. RUO is a seller’s statement of intended use, not an approval. Each term is defined below in a sentence or two.

Supplier pages and certificates use a lot of shorthand. This glossary explains the terms you will meet most often in this directory, in plain English. It describes what words mean on documents; it is not guidance on using any product.

Documents and testing

Certificate of analysis (COA): A laboratory report on a sample from one batch. It lists the tests run and the results. See how to read a COA.
Batch / lot number: The code for one production run. It should appear on both the vial and its certificate.
HPLC: High-performance liquid chromatography. Separates a sample into components; “purity” is usually the main peak’s share of the total.
Mass spectrometry (MS, LC-MS, ESI-MS): Measures molecular mass. Used to confirm identity — that the main component is the expected molecule.
Purity: A percentage from HPLC. It is a ratio, not an amount.
Net content / quantity: How much material was measured in the tested vial, in mg. Different from purity.
Counter-ion (acetate, TFA): A small ion paired with the peptide in the powder. It adds weight but does not appear in the HPLC purity figure.
Third-party testing: Testing by a laboratory independent of the seller. A report hosted on the laboratory’s own site is the strongest form of this.
In-house testing: Testing by the seller’s own laboratory. Useful, but not independent.
ISO/IEC 17025: The international standard for the competence of testing and calibration laboratories.

Formats and handling

Lyophilised: Freeze-dried. Water has been removed to slow degradation; the standard format for sealed research vials.
Pre-filled pen: A device holding the peptide already in solution. Suppliers in our directory deliver these within the UAE only.
Nasal spray: Another solution format; also UAE-only at the suppliers we list.
Bacteriostatic water: Sterile water with a preservative, sold as a laboratory supply.
Cold chain: Keeping products within a set temperature range throughout transport and storage.

Labels and regulation

RUO — research use only: The seller’s statement that a product is for laboratory research, not for human or veterinary use. It is not a regulatory approval and does not make an import legal.
GMP: Good manufacturing practice: the quality system regulators require for medicines. A research reagent sold as RUO is not a GMP medicine.
Registered medicine: A product assessed and approved by a national authority for a specific use.

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