Practical Protein Chemistry - A. Darbre 1989

Disulfide Bonds
Fractionation of Cystine-Containing Peptides
Fractionation Methods

Due to the stability of cystine-containing Peptides in a slightly acidic environment (pH 2.0–6.5), Gel filtration [8] and Ion-exchange Chromatography [2, 41] are used for fractionation. Gel filtration is performed on Sephadex in 25% acetic acid [17], and ion-exchange chromatography on cation exchangers [45]. During fractionation, it is primarily necessary to separate the cystine-containing peptides from one another, whereas separating them from other peptides is not strictly required [36, 41]. The remaining peptides can be easily removed at a subsequent stage, following The oxidation of cystine to cysteic acid. For instance, peptides containing cysteic acid can be efficiently fractionated using High-Performance Liquid Chromatography or ion-pair chromatography [23]. In the presence of phosphoric acid, nearly ideal resolution is achieved via chromatography on efficient columns in organic Solvents (Chapter 6).



Last update: 06/08/2026

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