Scavenger
Scavenger — A reagent added during peptide cleavage from resin to capture reactive cations and prevent side reactions that reduce yield and purity.
What Is a Scavenger?
A scavenger is a reagent added to the TFA cleavage cocktail that reacts with and neutralizes the reactive cations generated during side-chain protecting group removal. Without scavengers, these cations (tert-butyl, trityl, Pbf sulfonyl) can alkylate nucleophilic residues (Cys, Met, Trp), creating modified impurities.
Common Scavengers
- TIPS (triisopropylsilane): Effective cation scavenger. Standard in most modern cocktails
- Water: Scavenges tert-butyl cations. Always included at 2.5-5%
- EDT (ethanedithiol): Required for Arg(Pbf) and essential for Cys/Met-containing peptides
- Phenol: Scavenges carbocations. Included in Reagent K cocktails
- Thioanisole: Thioether scavenger for tert-butyl and Tmb cations
Frequently Asked Questions
What is Scavenger?
A reagent added during peptide cleavage from resin to capture reactive cations and prevent side reactions that reduce yield and purity.
Why is Scavenger important in peptide research?
Scavenger is a fundamental concept in synthesis as it relates to peptide science. It directly influences experimental design, compound characterization, and the reliability of research outcomes across biochemistry and molecular biology disciplines.