Peptide Glossary: A-Z Research Terms Explained

A comprehensive reference guide to the key terms, techniques, and compounds used in peptide research. Essential vocabulary for scientists working with synthetic peptides.

For research use only. All compounds listed are for in vitro laboratory research by qualified professionals only.

A

Acetylation

A chemical modification in which an acetyl group (CH3CO-) is added to a molecule. In peptide research, N-terminal acetylation improves metabolic stability of synthetic peptides. Examples include Snap-8 (Acetyl Octapeptide-3).

Acetic Acid

A weak organic acid used to dissolve peptides that are insoluble in water alone. Typically used at 0.1-1% concentration as a reconstitution solvent.

Amino Acid

The fundamental building blocks of peptides and proteins. Twenty standard amino acids exist, each with a unique side chain that determines its chemical properties. Peptides are chains of amino acids linked by peptide bonds, typically containing 2-50 residues.

AOD 9604

A modified fragment of human growth hormone (hGH), specifically residues 176-191 of the C-terminal region. Studied for its role in lipolysis and metabolic regulation in vitro. View AOD 9604.

ACTH (Adrenocorticotropic Hormone)

A peptide hormone produced by the pituitary gland. Several research peptides, including Semax, are synthetic analogues of ACTH fragments.

B

Bacteriostatic Water

Sterile water containing 0.9% benzyl alcohol as a preservative. The standard reconstitution solvent for most lyophilised research peptides. Benzyl alcohol inhibits microbial growth, extending the shelf life of reconstituted solutions. See our Reconstitution Guide.

BPC-157 (Body Protection Compound)

A synthetic pentadecapeptide (15 amino acids) derived from a protective protein found in gastric juice. Studied in vitro for angiogenesis, cell migration and nitric oxide signalling. One of the most extensively published peptides in preclinical literature. View BPC-157.

C

Certificate of Analysis (CoA)

A document confirming the identity, purity, and quality of a peptide batch. Includes HPLC purity data and mass spectrometry confirmation. Every order includes the CoA for its batch; sample certificates are in our CoA library.

CJC-1295

A synthetic analogue of growth hormone-releasing hormone (GHRH). CJC-1295 No DAC (also called Mod GRF 1-29) has a shorter active window, useful for pulse-based research. View CJC-1295 No DAC + Ipamorelin.

Copper Peptide

A peptide complexed with copper ions. The most studied copper peptide is GHK-Cu (Glycine-Histidine-Lysine copper complex), studied for copper-binding chemistry and extracellular matrix gene expression in vitro. View GHK-Cu.

D

DAC (Drug Affinity Complex)

A lysine linker that allows a peptide to bind to albumin, dramatically extending its half-life. CJC-1295 with DAC uses this mechanism; the No-DAC version has a shorter, pulsatile activity window.

DSIP (Delta Sleep-Inducing Peptide)

A nonapeptide first isolated from the cerebral venous blood of rabbits. Studied for its role in sleep regulation, neuromodulation, and stress response in vitro. View DSIP.

Disulfide Bond

A covalent bond formed between the sulfur atoms of two cysteine residues. Critical for the 3D structure and stability of many peptides. Peptides containing disulfide bonds require careful handling to avoid conditions that may disrupt their structure.

E

Epithalon (Epitalon)

A synthetic tetrapeptide (Ala-Glu-Asp-Gly) developed by the St. Petersburg Institute of Bioregulation and Gerontology. Studied for its influence on telomerase activity and telomere length in vitro. View Epithalon.

Elamipretide (SS-31)

A cell-permeable mitochondria-targeting tetrapeptide. Studied in vitro for its interaction with cardiolipin in the inner mitochondrial membrane and its effects on oxidative stress in cell models. View SS-31.

F

Freeze-Drying (Lyophilisation)

A preservation process in which water is removed from a peptide product under vacuum after freezing. Lyophilised peptides have superior long-term stability compared to liquid solutions. Our peptides are supplied as lyophilised powder in sealed vials.

G

GHK-Cu

Glycine-L-Histidine-L-Lysine copper complex. A naturally occurring tripeptide found in human plasma. Studied in vitro for extracellular matrix gene expression, collagen synthesis and antioxidant activity. View GHK-Cu.

GHRH (Growth Hormone-Releasing Hormone)

A peptide hormone produced by the hypothalamus that stimulates GH release from the pituitary. Synthetic GHRH analogues used in research include CJC-1295 and Tesamorelin.

GHRP (Growth Hormone-Releasing Peptide)

A class of synthetic peptides that stimulate GH release via the ghrelin receptor. Research GHRPs include Ipamorelin, GHRP-2, and GHRP-6. Often studied in combination with GHRH analogues.

GMP (Good Manufacturing Practice)

Regulations ensuring products are consistently produced and controlled according to quality standards. GMP peptides have reduced risk of contamination and batch-to-batch variability.

H

Half-Life

The time taken for the concentration of a peptide to reduce by 50% in a given system. Peptides typically have short half-lives due to enzymatic degradation by proteases. Modifications such as PEGylation or DAC linkers can extend half-life in research contexts.

HPLC (High-Performance Liquid Chromatography)

The gold-standard analytical technique for measuring peptide purity. HPLC separates compounds based on their interaction with a stationary and mobile phase. Results are expressed as a purity percentage. Each batch's purity is confirmed by HPLC and stated on its Certificate of Analysis.

I

Ipamorelin

A selective growth hormone secretagogue and GHRP. Noted for its receptor selectivity, making it useful for controlled GHS-R signalling research in vitro. View Ipamorelin.

In Vitro

Latin for outside a living organism. Refers to experiments conducted in a laboratory dish, test tube, or cell culture. All products supplied by Peptide Biosciences are for in vitro research use only.

K

Kisspeptin-10

A ten-amino-acid fragment of the kisspeptin neuropeptide family, encoded by the KISS1 gene. Acts on the GPR54 receptor and plays a key role in regulating the hypothalamic-pituitary-gonadal (HPG) axis. Studied in reproductive endocrinology research. View Kisspeptin-10.

KPV

A tripeptide (Lys-Pro-Val) derived from the C-terminal end of alpha-melanocyte-stimulating hormone. Studied in vitro for MC1R-mediated inflammatory signalling in epithelial and immune cell models. View KPV.

L

L-Carnitine

A naturally occurring amino acid derivative synthesised from lysine and methionine. Plays a key role in fatty acid transport into mitochondria for beta-oxidation. Studied in metabolic, cardiovascular, and mitochondrial research. View L-Carnitine.

Lyophilisation

See Freeze-Drying. Lyophilised peptides must be reconstituted before use - see our Reconstitution Guide.

M

Mass Spectrometry (MS)

An analytical technique measuring the mass-to-charge ratio of ions. Used alongside HPLC to confirm peptide identity (molecular weight) and detect impurities. A key component of any peptide Certificate of Analysis.

MOTS-C

A mitochondrial-derived peptide encoded by the 12S rRNA gene of mitochondrial DNA. Studied for its role in metabolic homeostasis, insulin sensitivity, and longevity in vitro. View MOTS-C.

N

NAD+ (Nicotinamide Adenine Dinucleotide)

A coenzyme central to energy metabolism and signalling pathways including sirtuins, PARP enzymes, and CD38. NAD+ levels decline with age, making it a focus of longevity research. View NAD+.

NNMT (Nicotinamide N-Methyltransferase)

An enzyme involved in the methylation of nicotinamide. NNMT inhibition has been studied in the context of metabolic disorders. 5-Amino-1MQ is a research compound that selectively inhibits NNMT. View 5-Amino-1MQ.

P

PDRN (Polydeoxyribonucleotide)

A biopolymer derived from salmon sperm DNA. Acts as a purinergic A2A receptor agonist and extracellular DNA scaffold, and is studied for adenosine receptor signalling in cell models.

Peptide

A short chain of amino acids (typically 2-50 residues) linked by peptide bonds. Distinguished from proteins, which are generally larger and more complex. Peptides are the focus of rapidly growing biomedical research due to their high specificity and targeted biological activity.

Peptide Bond

A covalent bond formed between the carboxyl group of one amino acid and the amino group of another, releasing a water molecule. Peptide bonds form the backbone of all peptide and protein chains.

PT-141 (Bremelanotide)

A cyclic heptapeptide melanocortin receptor agonist. Studied for MC3R and MC4R receptor pharmacology in vitro. View PT-141.

Purity (%)

A measure of the proportion of the desired compound in a sample, expressed as percentage area under the HPLC curve. Purity varies by compound and is stated on each batch's Certificate of Analysis, from independent third-party HPLC testing.

R

Reconstitution

The process of dissolving a lyophilised peptide powder in a solvent - most commonly sterile or bacteriostatic water. See our Peptide Reconstitution Guide for step-by-step instructions.

Research Chemical

A compound supplied strictly for in vitro scientific research by qualified professionals. Not approved for human or veterinary use. All products from Peptide Biosciences are supplied under this classification.

S

Selank

A synthetic heptapeptide analogue of the endogenous neuropeptide tuftsin. Developed by the Institute of Molecular Genetics of the Russian Academy of Sciences. Studied for GABAergic and neuroimmune signalling in neurological research. View Selank.

Semax

A heptapeptide derived from ACTH(4-10). Studied for neurotrophic signalling, neuroplasticity, and BDNF expression in vitro. View Semax.

SLU-PP-332

A small molecule agonist of the estrogen-related receptors. Studied in vitro for its effects on muscle fibre composition and fatty acid oxidation in cell models. View SLU-PP-332.

Snap-8 (Acetyl Octapeptide-3)

A synthetic octapeptide extension of Argireline. Competitively inhibits the SNARE complex involved in neurotransmitter release. Studied in cosmetic skin biology research. View Snap-8.

T

TB-500 (Thymosin Beta-4)

A synthetic fragment based on the naturally occurring 43-amino-acid peptide Thymosin Beta-4. Studied in vitro for actin binding, cell migration and angiogenesis. View TB-500.

Tesamorelin

A 44-amino-acid synthetic analogue of GHRH. Studied for GHRH-receptor pharmacology and GH secretion in research contexts. View Tesamorelin.

W

Water for Injection (WFI)

A pharmacopoeial grade of highly purified, sterile water. In the laboratory it is used as a high-purity solvent; bacteriostatic water is WFI with 0.9% benzyl alcohol added as a preservative.

This glossary is for educational reference only. All products referenced are for in vitro laboratory research use only by qualified professionals. Not for human or veterinary administration. Peptide Biosciences does not provide medical advice.