Peptide Terminology Glossary: A Beginner's Guide

Amino Acid: The building blocks of peptides and proteins — 20 standard amino acids exist in nature. Peptide Bond: The chemical bond between two amino acids. Sequence: The order of amino acids in a peptide, written from the N-terminal (amino-) to C-terminal (carboxy-) end. Molecular Weight (MW): The mass of the molecule in Daltons (Da) — peptides typically range from 200 Da to 5,000 Da.

Lyophilization (Freeze-drying): A dehydration process under vacuum that converts the peptide into a stable powder. Vial: The sealed glass container holding lyophilized peptide. Bacteriostatic Water (BAC Water): Sterile water with 0.9% benzyl alcohol — used for multi-dose reconstitution. Sterile Water: Pure water without preservatives — for single-dose use.

Reconstitution: The process of dissolving lyophilized peptide in liquid. Concentration: The amount of peptide per unit volume (e.g., mg/mL). Subcutaneous (SubQ): A route classification referring to tissue beneath the skin in pharmacological literature. Intramuscular (IM): A route classification referring to muscle tissue. Insulin Syringe: A volume-measurement device calibrated in Units (IU) — 100 IU = 1 mL on a U-100 scale.

Protocol: A structured guide describing dosage, frequency, cycle duration, and route of administration. Cycle: The time period of protocol use (e.g., 8 weeks on, 4 weeks off). Half-life: The time required for the peptide concentration to decrease by half. Loading Dose: An initial higher dose for faster achievement of therapeutic range. Maintenance Dose: The steady dose after the loading phase.

GH Secretagogues: Peptides that stimulate growth hormone release (e.g., Ipamorelin, GHRP-6). GLP-1 Agonists: Mimic the GLP-1 hormone for metabolic regulation (e.g., Semaglutide). Bioregulators: Ultrashort peptides (2–4 AA) that regulate gene expression (e.g., Epithalon, Thymalin). Nootropics: Peptides studied for cognitive support (e.g., Selank, Semax). Healing Peptides: Peptides for musculoskeletal recovery (e.g., BPC-157, TB-500).