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A modified procedure for caseinophosphopeptide analysis.

J H Lin·B H Chiang
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Abstract

A modified procedure is established for analyzing caseinophosphopeptides. The sodium caseinate hydrolysate is first treated by immobilized metal ion affinity chromatography to enrich the phosphopeptides. Because of the formation of Fe(3+)-peptide complexes, ethylenediaminetetraacetic acid is added to the bound fraction eluted with the immobilized metal ion affinity chromatography to disintegrate the complexes. Thus, the subsequent high-performance liquid chromatographic analysis is facilitated. A stepwise gradient elution is also suggested to enhance the resolution of caseinophosphopeptides during high-performance liquid chromatographic analysis.

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Amino Acid SequenceCaseinsChromatography, AffinityChromatography, High Pressure LiquidEdetic AcidMolecular Sequence DataPhosphopeptidesProtein HydrolysatesTrypsinJournal ArticleResearch Support, Non-U.S. Gov't

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J H Lin, B H Chiang. 1996. A modified procedure for caseinophosphopeptide analysis.. https://doi.org/10.1093/chromsci%2F34.8.358

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