Research Peptide Glossary

An organic molecule containing both an amino group and a carboxyl group. There are 20 standard amino acids that serve as the building blocks of all peptides and proteins. The sequence of amino acids determines the structure and function of a peptide.

A chemical modification in which an acetyl group is added to the N-terminus or a side chain of a peptide. N-terminal acetylation can improve metabolic stability by protecting the peptide from amino peptidase enzymes.

A chemical modification in which the C-terminus of a peptide is converted to an amide group. C-terminal amidation can improve stability against carboxypeptidase enzymes and may affect receptor binding characteristics.

The formation of new blood vessels from pre-existing ones. Angiogenesis is studied in the context of wound healing, tissue repair, and tumour biology. Certain research peptides are investigated for their ability to modulate angiogenic signalling pathways.

Programmed cell death, a regulated process by which cells activate an internal sequence of events that leads to their orderly disassembly. Apoptosis is distinct from necrosis and plays roles in development, tissue maintenance, and disease. Research compounds are studied for their ability to induce or inhibit apoptotic pathways.

An enzyme that acts as a cellular energy sensor. When cellular energy levels are low (high AMP:ATP ratio), AMPK is activated and promotes pathways that generate ATP while inhibiting energy-consuming processes. AMPK activation is studied as a mechanism of action for several metabolic research peptides.

The UK's independent regulator of advertising across all media. The ASA applies the UK Code of Non-broadcast Advertising and Direct and Promotional Marketing (CAP Code) to marketing materials, including websites. Advertisers of research compounds must ensure claims are accurate, substantiated, and do not imply health benefits for humans.

A unique identifier assigned to a specific production run of a compound. The batch number links a physical vial to its corresponding Certificate of Analysis, enabling traceability and quality verification.

Sterile water containing 0.9% benzyl alcohol, which inhibits bacterial growth. It is the standard diluent used in research settings when preparing peptide solutions for use over an extended period, as the preservative extends the stability of the reconstituted solution.

The proportion of an administered compound that reaches the target tissue in an active form, relative to the administered dose. Bioavailability is studied in the context of the route of administration and the compound's susceptibility to degradation before reaching the site of interest.

A document issued by a testing laboratory stating the analytical results for a specific batch of material. For research peptides, a COA typically records purity by HPLC, molecular weight confirmation, and batch identification. It provides traceability between a physical vial and the test data for that production run.

The biological process by which cells produce collagen, a structural protein that is the main component of connective tissue. Research into collagen synthesis examines compounds that modulate fibroblast activity, procollagen gene expression, or the post-translational processing steps that convert procollagen into mature collagen fibres.

A temperature-controlled supply chain for perishable or sensitive goods. For research peptides, maintaining the cold chain from manufacturer to laboratory typically means storing and shipping at 2–8°C (refrigerated) or -20°C (frozen), depending on the compound and whether it has been reconstituted.

Certain peptides and research compounds are controlled under the Misuse of Drugs Act 1971 or other UK legislation. Regulatory status can change and researchers should verify the current legal status of any compound before procurement. Most research peptides sold by Peptify UK are not controlled substances but are sold solely for in-vitro research use.

A covalent bond formed between two cysteine residues via their sulfhydryl groups. Disulfide bonds contribute to the three-dimensional structure of peptides and proteins and can influence stability and biological activity.

The process by which a compound undergoes chemical changes that reduce its purity or alter its structure. For peptides, degradation can occur via hydrolysis of peptide bonds, oxidation of susceptible residues (e.g., methionine, tryptophan), or enzymatic cleavage.

Preservation of a compound at temperatures below 0°C, typically -20°C for medium-term storage or -80°C for long-term archival. Freezer storage slows chemical degradation by reducing molecular motion and inhibiting enzymatic and microbial activity.

A 191-amino acid peptide produced by the anterior pituitary gland. GH regulates growth, metabolism, and body composition. Its secretion is pulsatile and stimulated by growth hormone-releasing hormones (GHRHs) and growth hormone-releasing peptides (GHRPs). Research into GH secretagogues examines how synthetic peptides can stimulate endogenous GH release.

A naturally occurring copper-binding tripeptide composed of glycine, histidine, and lysine. GHK-Cu is found in human plasma, saliva, and urine. It is researched for its roles in activating fibroblasts, stimulating collagen and glycosaminoglycan synthesis, and modulating tissue remodelling processes.

An incretin hormone produced by intestinal L-cells in response to nutrient intake. GLP-1 stimulates insulin secretion, suppresses glucagon release, slows gastric emptying, and reduces appetite. GLP-1 receptor agonists are a major focus of metabolic research.

A hypothalamic peptide that stimulates growth hormone synthesis and secretion from the anterior pituitary. Synthetic GHRH analogues are researched for their capacity to stimulate pulsatile GH release in experimental models.

A class of synthetic peptides that stimulate GH secretion through the ghrelin receptor (GHSR-1a). Unlike GHRH analogues, GHRPs act through a distinct receptor pathway. Research GHRPs include GHRP-2, GHRP-6, Ipamorelin, and Hexarelin.

A system of regulations and quality standards that governs the manufacture of pharmaceutical and other regulated products. GMP certification is granted by regulatory bodies (e.g., MHRA in the UK) and requires documented quality systems, validated processes, and traceability. Research chemicals manufactured without GMP certification are not approved for medicinal use.

High-Performance Liquid Chromatography. An analytical technique in which a sample is dissolved in a solvent and pushed under pressure through a column packed with adsorbent material. Different compounds elute at different rates, allowing their identity and quantity to be determined. Used to confirm peptide purity as a percentage of the total sample.

The time required for the concentration of a compound to decrease to half its original value in a given system. In research pharmacokinetics, a longer half-life indicates slower clearance from the system being studied. Peptide half-lives vary widely depending on structure and resistance to enzymatic degradation.

Latin for 'in glass'. Refers to experiments conducted in a controlled environment outside a living organism, such as in a test tube, cell culture dish, or other laboratory vessel. In-vitro studies are used to investigate how compounds interact with cells, tissues, or biochemical systems.

Latin for 'within the living'. Refers to research conducted within a living organism. In-vivo studies observe how compounds behave in a complete biological system, including absorption, distribution, metabolism, and excretion.

A peptide hormone that is structurally similar to insulin. IGF-1 is produced primarily in the liver in response to growth hormone signalling. It mediates many of the anabolic effects of growth hormone and activates the PI3K/Akt and MAPK/ERK signalling pathways, which are studied in the context of cell growth and differentiation.

Describes a substance that has been freeze-dried: the water content is removed by first freezing the material and then applying a vacuum so that the ice transitions directly to vapour without passing through a liquid phase. Lyophilisation produces a stable powder that is easier to store and transport than a liquid solution.

An industrial process that removes moisture from a frozen material by sublimation under vacuum. The result is a dry, stable powder that retains the chemical structure of the original compound. Lyophilisation is the standard preservation method for research peptides because it extends shelf life without the need for refrigeration during transport.

An analytical technique that ionises chemical compounds and sorts the resulting ions by their mass-to-charge ratio. For peptides, mass spectrometry confirms molecular weight and therefore the identity of the compound, complementing HPLC purity data.

The sum of the atomic weights of all atoms in a molecule, expressed in Daltons (Da) or grams per mole (g/mol). Confirming the molecular weight of a synthesised peptide via mass spectrometry verifies that the correct compound was produced.

Organelles present in most eukaryotic cells that produce ATP via oxidative phosphorylation. Mitochondria have their own DNA and membrane system. Mitochondrial function is studied in the contexts of energy metabolism, ageing, and oxidative stress.

The UK government agency responsible for regulating medicines, medical devices, and blood components for transfusion. The MHRA is the primary regulatory body overseeing medicinal claims in the United Kingdom. Research peptides sold for in-vitro use only are not regulated as medicines by the MHRA.

A coenzyme found in all living cells that participates in redox reactions as an electron carrier. NAD+ is required for the activity of sirtuins and PARPs, enzymes involved in gene regulation, DNA repair, and metabolic signalling. NAD+ levels decline with age, making it a subject of longevity research.

The proportion of the target compound relative to all detectable substances in a sample, typically expressed as a percentage by HPLC peak area. A result of 99%+ indicates that at least 99 parts in every 100 are the desired compound.

A short chain of amino acids linked by peptide bonds. Peptides are smaller than proteins (typically fewer than 50 amino acids) and can be synthesised in a laboratory. In research contexts, synthetic peptides are used to study biological signalling pathways.

A covalent chemical bond formed between the carboxyl group of one amino acid and the amino group of another, with the release of a water molecule. Peptide bonds are the primary structural linkage in all peptides and proteins.

The time elapsed from sample injection to the appearance of a compound's peak in HPLC chromatography. Each compound has a characteristic retention time under defined conditions, which contributes to its identification.

The act of mixing a lyophilised (freeze-dried) powder with a suitable diluent such as bacteriostatic water to form a liquid solution. In research laboratory practice, reconstitution returns the compound to a usable solution form for in-vitro experiments.

A compound that binds to a receptor and activates it, producing a biological response. Research agonists are used to investigate the downstream effects of receptor activation in cellular and animal models.

A classification indicating that a product is intended solely for in-vitro research or laboratory investigations and is not approved or intended for use in humans or animals. RUO designation means the compound has not undergone the clinical trials required for regulatory approval as a medicine.

The ability of a substance to dissolve in a given solvent to form a homogeneous solution. Peptide solubility depends on the amino acid sequence, pH of the solvent, and temperature. Some peptides require the addition of a small volume of dilute acid or DMSO before adding water.

A peptide produced by chemical synthesis in a laboratory rather than extracted from a biological source. Solid-phase peptide synthesis (SPPS) is the primary method, allowing precise control over amino acid sequence and therefore structure.

A laboratory method for building a peptide chain by sequentially adding protected amino acids to a resin-bound growing chain. After assembly, the peptide is cleaved from the resin and purified. SPPS is the industry standard for producing research-grade synthetic peptides.

A compound that stimulates the secretion of another substance. In peptide research, growth hormone secretagogues are compounds studied for their ability to stimulate the pituitary gland to release growth hormone.

A family of NAD+-dependent deacetylase enzymes (SIRT1–7) that regulate gene expression, DNA repair, and metabolic processes. Sirtuins require NAD+ as a substrate; research into NAD+ supplementation is partly motivated by the aim of supporting sirtuin activity.

The degree to which a compound retains its chemical identity and potency under specified conditions over time. Peptide stability is affected by temperature, light, humidity, pH, and the presence of proteases. Stability data are typically expressed as the percentage of original purity retained at a given time point under defined storage conditions.

Analysis performed by an independent laboratory that has no commercial relationship with the manufacturer of the product being tested. Third-party results are considered more objective than in-house testing and are standard practice for research-grade compounds.

An enzyme that extends telomeres — the protective caps at the ends of chromosomes. Telomere length decreases with each cell division; telomerase can reverse this process. The study of telomerase activation is a focus of cellular longevity research.

The property of a molecule to absorb ultraviolet light at a characteristic wavelength. In HPLC analysis, a UV detector measures how much light is absorbed as each compound passes through, generating a peak whose area is proportional to the quantity of that compound.