Glossary · 2026-09-24
By Alice Kay · Last reviewed 24 Sep 2026
Disulfide bridge, laboratory definition
Research-use notice: This article summarizes published scientific literature for educational purposes. It is not medical advice and does not provide dosing, administration or human-use information. Findings described in the literature do not apply to any BlueNex Labs product, which is supplied only for in-vitro laboratory research and not for human or animal use.
A disulfide bridge is a covalent bond between two sulfur atoms, usually the side chains of two cysteine residues. It can close a ring in one chain or tie two chains together. It changes the mass relative to two free thiols, so an identity calculation has to state whether the cystines are bridged. This glossary does not assign that form from a product name.
The BPC-157 sequence published on this site, GEPPPGKPADDAGLV, contains no cysteine, so that string does not describe an intramolecular disulfide. Read sequence and bonding in peptide structure and stability and structural peptides. Confirm any bridge only when the lot file's mass species says so. Research use only.
Published lot files for this catalogue are indexed in the certificates library. This definition does not add a report, and it does not assign a task identifier. Research use only.
Frequently asked questions
- Does every research peptide in the catalogue have a disulfide?
- No. Infer a bridge only from a sequence that contains cysteine and from a mass species the report names. A product title is not that evidence.
- Is a disulfide the same as a peptide bond?
- No. A peptide bond links residues along the chain. A disulfide is a side-chain S–S bond. They are different links.
Research use only. BlueNex Labs does not provide medical or veterinary advice. Confirm your institution’s policies before purchase. How a comparison or class note is checked sits on documentation standards. Articles are written and reviewed by Alice Kay, Ph.D.