FAQ & Glossary
Questions answered, terms explained.
Common questions about peptides, their use, and the research behind them — plus a plain-language glossary of the terminology you'll encounter across this site.
Frequently asked
12 questions across 4 topics.
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Glossary
15 terms defined in plain language.
- Amino acid
- The molecular building blocks of proteins and peptides. There are 20 standard amino acids. The sequence and length of amino acid chains determines the structure and function of the resulting peptide or protein.
- Angiogenesis
- The formation of new blood vessels from existing ones. Several healing peptides (particularly BPC-157) promote angiogenesis at injury sites, which accelerates tissue repair by improving blood supply and nutrient delivery.
- Bacteriostatic water (BW)
- Sterile water containing 0.9% benzyl alcohol, which prevents bacterial growth. Used to reconstitute lyophilised peptides. The benzyl alcohol preservative allows the reconstituted solution to be stored for up to 28–30 days in the fridge, unlike plain sterile water.
- Bioavailability
- The proportion of a substance that enters the bloodstream and is able to have an active effect. Subcutaneous injection typically achieves near-100% bioavailability for peptides. Oral bioavailability is very low for most peptides because digestive enzymes break them down before absorption.
- Certificate of Analysis (CoA)
- A document from an independent laboratory confirming the identity, purity, and potency of a compound. A CoA from a reputable third-party lab (not the supplier's own lab) is the minimum standard of quality assurance when sourcing research peptides.
- GH secretagogue
- A compound that stimulates the secretion of growth hormone (GH) from the pituitary gland. Peptide secretagogues include GHRH analogues (like CJC-1295) and GHRPs (like Ipamorelin). They work by amplifying the body's natural GH pulses rather than introducing exogenous GH directly.
- GLP-1 agonist
- A compound that mimics glucagon-like peptide-1 (GLP-1), a hormone released after eating that regulates appetite and blood sugar. GLP-1 agonists like Semaglutide slow gastric emptying, reduce appetite, and stimulate insulin secretion. They are used for type 2 diabetes and weight management.
- Half-life
- The time it takes for the concentration of a substance in the body to reduce by half. A peptide with a short half-life (e.g. Ipamorelin at ~2 hours) needs more frequent dosing than one with a long half-life (e.g. Semaglutide at ~7 days). Half-life influences dosing frequency and cycle design.
- HPLC (High-Performance Liquid Chromatography)
- A laboratory technique used to separate, identify, and quantify components in a mixture. HPLC testing on a peptide CoA confirms purity — typically expressed as a percentage (e.g. 98.5% pure). It is the gold standard for verifying peptide quality.
- IGF-1 (Insulin-like Growth Factor 1)
- A hormone produced primarily by the liver in response to growth hormone stimulation. IGF-1 mediates many of GH's anabolic effects — promoting muscle growth, fat metabolism, and tissue repair. GH secretagogue peptides raise GH levels, which in turn raises IGF-1.
- Lyophilised
- Freeze-dried. Most research peptides are supplied as lyophilised white powder, which is stable at room temperature and has a long shelf life. Before use, lyophilised peptides must be reconstituted by adding bacteriostatic water.
- MHRA
- Medicines and Healthcare products Regulatory Agency. The UK government body responsible for regulating medicines, medical devices, and blood components. A peptide approved by the MHRA is a licensed medicine in the UK. Most research peptides are not MHRA-approved.
- Peptide bond
- The chemical bond that links amino acids together in a chain. Formed between the carboxyl group of one amino acid and the amino group of the next, with the release of a water molecule. The sequence of peptide bonds determines the peptide's three-dimensional structure and biological activity.
- Subcutaneous (SubQ)
- Beneath the skin, into the fatty tissue layer. Subcutaneous injection is the most common administration route for research peptides. It uses a short (4–6mm) insulin needle inserted at a 45–90° angle into the skin fold, typically at the abdomen, thigh, or upper arm.
- Telomerase
- An enzyme that maintains and extends telomeres — the protective caps at the ends of chromosomes. Telomere shortening is associated with cellular ageing. Epithalon is believed to stimulate telomerase activity, which is the basis of its proposed anti-aging effects.
Important: All content is for informational purposes only. Not medical advice. Always consult a qualified healthcare professional before starting any peptide protocol.