An oligopeptide is a short chain of 2 to roughly 20 amino acids linked by peptide bonds. This intermediate category covers a very broad swath of the peptide universe, encompassing dipeptides, tripeptides and longer chains up to the fuzzy boundary with polypeptides. The upper limit is not strictly standardized — some authors use 10 residues, others 20, still others 50.
This range hosts most bioactive peptides in living organisms. Enkephalins (5 aa, endogenous opioid neuropeptides), substance P (11 aa, proinflammatory neuropeptide), vasopressin (9 aa, antidiuretic hormone), oxytocin (9 aa, neurohypophyseal hormone), somatostatin (14 aa, hormonal inhibitor), angiotensin II (8 aa, blood pressure regulator), bradykinin (9 aa, vasodilator), gastrin (14 or 34 aa depending on form) — all oligopeptides founding entire sections of modern physiology and pharmacology.
On the research and catalog side, most therapeutically relevant peptides studied under RUO sit in this range. BPC-157 (15 aa) is an oligopeptide. TB-500 fragment 17-23 (7 aa) is one too. GHK-Cu (3 aa), melanotan II (7 aa), ipamorelin (5 aa), CJC-1295 without DAC (30 aa, at the upper boundary), PT-141 (7 aa): the bulk of current peptide research plays out between 5 and 30 amino acids.
This range offers an optimal balance between functional complexity (sufficient to carry minimal secondary structure, high affinity and selectivity), synthesis feasibility (accessible via SPPS with high yield), reasonable stability and controlled cost. Beyond 30-40 residues, synthesis yields drop, impurities accumulate and purification becomes a major technical challenge.
Oligopeptides thus represent the core of a peptide catalog: maximum scientific value for an industrially manageable production cost.
Décryptez la caractérisation complète d'un peptide : RP-HPLC préparative et analytique, LC-MS haute résolution Orbitrap/QTOF, RMN 2D (COSY/TOCSY/NOESY), dégradation d'Edman, cartographie peptidique MS/MS, dichroïsme circulaire. Les 10 techniques qui séparent un peptide research-grade d'un peptide douteux, avec seuils de détection et stratégie de QC.
Maitrisez les mecanismes qui detruisent vos peptides : oxydation Met, deamidation Asn, hydrolyse, aggregation. Protocoles de lyophilisation, conditions de stockage, reconstitution optimale et QC shelf-life. Le pilier technique que tout laboratoire doit integrer pour garantir l'integrite de ses peptides en recherche exploratoire.
Principe Merrifield, stratégies Fmoc et Boc, résines (Wang, Rink amide, 2-chlorotrityl), agents de couplage (HBTU, HATU, DIC/HOBt), cycle de synthèse, clivage TFA, purification RP-HPLC, contrôle qualité LC-MS et test Kaiser. Le pilier scientifique de référence sur la fabrication des peptides synthétiques.