A-C
Amino Acid: The building blocks of peptides and proteins. Twenty standard amino acids are encoded by DNA, each with distinct chemical properties.
Amidation: A chemical modification of the C-terminus converting the carboxyl group to an amide. Improves resistance to enzymatic degradation.
Acetylation: Addition of an acetyl group to the N-terminus. Protects against aminopeptidase activity and can improve stability.
Bacteriostatic Water (BAC Water): Sterile water containing 0.9% benzyl alcohol as a preservative. Standard reconstitution solvent for research peptides.
Bioavailability: The fraction of an administered compound that reaches systemic circulation. Relevant in pharmacokinetic research studies.
Certificate of Analysis (COA): A document reporting the results of quality testing for a specific batch. Should include HPLC purity, mass spectrometry data, and lot number.
Chromatogram: The graphical output of an HPLC or other chromatographic analysis. Shows peaks corresponding to separated components.
Coupling: The chemical reaction that forms a peptide bond between two amino acids during synthesis.
Crude Peptide: The unpurified product after cleavage from the synthesis resin. Typically 70-85% pure before HPLC purification.
D-H
Dalton (Da): The unit of molecular weight. A dalton equals approximately the mass of one hydrogen atom. BPC-157 has a molecular weight of approximately 1419 Da.
Deamidation: Conversion of asparagine to aspartate or isoaspartate. A common degradation pathway that can affect peptide activity.
DPP-4 (Dipeptidyl Peptidase-4): An enzyme that rapidly degrades GLP-1 and GIP. DPP-4 resistance is engineered into modified incretin analogs.
Disulfide Bond: A covalent bond between two cysteine residues. Important for the structural integrity of many peptides.
ELISA: Enzyme-Linked Immunosorbent Assay. A plate-based technique for detecting and quantifying peptides using antibodies.
Fmoc (Fluorenylmethyloxycarbonyl): The most common protecting group used in modern solid-phase peptide synthesis.
GLP-1 (Glucagon-Like Peptide-1): An incretin hormone that enhances insulin secretion and reduces appetite. Target of several research peptide compounds.
GIP (Glucose-dependent Insulinotropic Polypeptide): An incretin hormone that potentiates insulin secretion and affects lipid metabolism.
HPLC (High-Performance Liquid Chromatography): The primary analytical method for determining peptide purity. Separates compounds based on their interaction with a stationary phase.
I-P
In Vitro: Research conducted in a controlled environment outside a living organism, such as in cell cultures, test tubes, or well plates.
In Vivo: Research conducted in living organisms, including animal models.
Lyophilization: Freeze-drying. The standard preservation method for research peptides. Removes water through sublimation under vacuum.
MALDI-TOF: Matrix-Assisted Laser Desorption/Ionization Time-of-Flight mass spectrometry. Used to confirm peptide identity by measuring molecular weight.
Molecular Weight (MW): The sum of atomic weights of all atoms in a molecule. Used to confirm peptide identity via mass spectrometry.
N-terminus: The amino end of a peptide chain. The conventional starting point when writing sequences.
C-terminus: The carboxyl end of a peptide chain. The conventional ending point when writing sequences.
Peptide Bond: The covalent amide bond between the carboxyl group of one amino acid and the amino group of the next.
Protecting Group: A chemical group temporarily attached to reactive amino acid side chains during synthesis to prevent unwanted reactions.
Purity: The percentage of the sample that is the target peptide, as measured by HPLC area percent.
R-Z
Reconstitution: The process of dissolving a lyophilized peptide in solvent (typically bacteriostatic water) for use.
Retention Time: The time a compound takes to travel through an HPLC column. Characteristic for each peptide under defined conditions.
Reverse-Phase HPLC (RP-HPLC): The most common HPLC mode for peptides. Separates compounds based on hydrophobicity.
Sequence: The ordered list of amino acids in a peptide, written from N-terminus to C-terminus.
Solid-Phase Peptide Synthesis (SPPS): The standard method for manufacturing research peptides. Amino acids are added sequentially to a resin-bound growing chain.
Sublimation: The phase transition from solid directly to gas. The mechanism by which water is removed during lyophilization.
TFA (Trifluoroacetic Acid): Used in peptide synthesis cleavage and as an HPLC mobile phase additive. Trace TFA may be present as a counter-ion in lyophilized peptides.
Truncated Sequence: An incomplete peptide where synthesis terminated before the full sequence was completed. The most common impurity in SPPS products.
