A Simple Approach to Assign Disulfide Connectivity for Ziconotide via Partial Reduction Without Alkylation

A relatively simple method based on partial reduction without alkylation, followed by analysis with liquid chromatography-tandem mass spectrometry, was developed, assigning disulfide connectivity for a disulfide-rich peptide. This method is useful in the quality control of medicinal peptides with an extensive disulfide network.