Peptide Glossary

A peptide is a short chain of amino acids linked together by peptide bonds — smaller than a full protein. In research, peptides are studied for their role as signaling molecules that interact with specific receptors in biological systems.

Amino acids are small organic molecules that link together to form peptides and proteins. There are 20 standard amino acids that make up nearly every peptide found in nature.

Lyophilization (freeze-drying) is the process of removing water from a peptide under vacuum at very low temperature. The result is a stable powder that ships and stores far better than a liquid solution.

Reconstitution is the process of adding a sterile solvent — typically bacteriostatic water — to a lyophilized peptide vial so it becomes a liquid solution suitable for research use.

Bacteriostatic water is sterile water containing 0.9% benzyl alcohol as a preservative. The preservative inhibits bacterial growth, extending the usable window of a reconstituted peptide compared with plain sterile water.

High-Performance Liquid Chromatography (HPLC) separates the compounds in a sample by pushing them through a column at high pressure. It is the standard analytical method for determining the purity percentage reported on a peptide COA.

Mass spectrometry ionizes molecules and measures their mass-to-charge ratio, letting a lab confirm that the dominant peak identified by HPLC actually matches the target peptide's expected molecular weight.

A Certificate of Analysis is a document issued by an independent laboratory that reports the purity, identity, and batch information of a specific peptide lot. Warrior Labs publishes COAs for every batch we ship.

Purity is the percentage of the material in the vial that is the intended peptide sequence, with the remainder being trace impurities from synthesis. ≥ 99% is considered research grade.

A receptor agonist binds to a specific cellular receptor and activates it, mimicking the action of the body's natural signaling molecule for that receptor. Many research peptides are studied for their receptor agonism at specific targets.

GLP-1 (Glucagon-Like Peptide-1) is an incretin hormone receptor pathway studied for its role in glucose regulation, insulin release, and appetite signaling. Peptides such as Tirzepatide and Retatrutide are studied as GLP-1 receptor agonists among other targets.

GIP is a second incretin hormone receptor. Dual and triple agonists such as Tirzepatide (GIP/GLP-1) and Retatrutide (GIP/GLP-1/glucagon) are studied for combined receptor activity across metabolic pathways.

The glucagon receptor pathway is studied for its role in hepatic glucose output and energy expenditure. It is the third target in triple agonists such as Retatrutide.

BPC-157 is a 15-amino-acid peptide fragment originally identified in gastric juice, studied in animal models for tissue repair and gastrointestinal protection.

TB-500 is a synthetic peptide fragment derived from Thymosin Beta-4, studied for its role in cellular migration and tissue repair processes in research models.

GHK-Cu is a naturally occurring copper-binding tripeptide (glycyl-L-histidyl-L-lysine complexed with copper) studied for its role in skin remodeling and wound-healing pathways.

HCG is a glycoprotein hormone studied in endocrine research for its role in signaling Leydig cell activity and its use alongside testosterone-related research protocols.

PT-141 is a synthetic peptide studied as an agonist at melanocortin receptors, investigated in research contexts related to central nervous system signaling.

MT-2 is a synthetic analog of alpha-melanocyte stimulating hormone, studied in research settings for its interaction with melanocortin receptors and pigmentation pathways.

Oxytocin is a naturally occurring 9-amino-acid neuropeptide studied for its role in social bonding, stress response, and neuroendocrine signaling.

Mots-C is a 16-amino-acid peptide encoded within mitochondrial DNA, studied in longevity and metabolic research for its role in cellular energy regulation.

Retatrutide is a synthetic peptide studied as a triple agonist at the GIP, GLP-1, and glucagon receptors — investigated for its combined effects on metabolic research endpoints.

Tirzepatide is a synthetic peptide studied as a dual agonist at GIP and GLP-1 receptors, investigated for its role in glucose and body-composition research.

Research Use Only products are sold as reference standards for in-vitro laboratory research. They are not drugs, dietary supplements, or medical devices, and are not intended for human or veterinary use.