From sequence to structure
A peptide's primary structure is its amino acid sequence. Local folding — helices, turns, sheets — forms the secondary structure that a receptor actually recognises. Small sequence changes can abolish or amplify activity.
Cyclisation, disulfide bridges, and non-natural amino acids are common strategies for locking a peptide into an active shape and protecting it from enzymes.
Fig. 02 / Molecular pathwaySynthesis and purity
Most research and pharmaceutical peptides are made by solid-phase peptide synthesis, then purified by chromatography and characterised by mass spectrometry.
Purity is a practical safety issue, not a technicality. Truncated sequences, residual solvents, endotoxin, and incorrect counterion content are real failure modes — and they are the reason pharmaceutical-grade manufacturing exists.
- Certificates of analysis vary widely in rigour and can be fabricated.
- Purity by HPLC does not establish sterility or endotoxin limits.
- Identity confirmation requires mass spectrometry, not a product label.
Editorial disclaimer
This site is educational and does not provide medical advice, dosing protocols, or treatment recommendations. Regulatory status and evidence strength differ sharply between compounds. A “research use only” label does not indicate that a product is appropriate for human use. Decisions about medicines belong with a qualified clinician.