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Characterization of cyclic peptides containing disulfide bonds.

ABSTRACT: Unlike linear peptides, analysis of cyclic peptides containing disulfide bonds is not straightforward and demands indirect methods to achieve a rigorous proof of structure. Three peptides that belong to this category, p-Cl-Phe-DPDPE, DPDPE, and CTOP, were analyzed and the results are presented in this paper. The great potential of two dimensional NMR and ESI tandem mass spectrometry was harnessed during the course of peptide characterizations. A new RP-HPLC method for the analysis of trifluoroacetic acid is also presented. It is robust, simple, and efficient compared to the currently available methods.

SUBMITTER: Johnson M

PROVIDER: S-EPMC4608431 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Characterization of cyclic peptides containing disulfide bonds.

Johnson Mindy M Liu Mingtao M Struble Elaine E Hettiarachchi Kanthi K

Journal of pharmaceutical and biomedical analysis 20150122

Unlike linear peptides, analysis of cyclic peptides containing disulfide bonds is not straightforward and demands indirect methods to achieve a rigorous proof of structure. Three peptides that belong to this category, p-Cl-Phe-DPDPE, DPDPE, and CTOP, were analyzed and the results are presented in this paper. The great potential of two dimensional NMR and ESI tandem mass spectrometry was harnessed during the course of peptide characterizations. A new RP-HPLC method for the analysis of trifluoroac ...[more]

PMID: 25778927

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