Method and kit for the isolation of phosphorylated peptides

Method for the enrichment of phosphopeptides, comprising of the following method steps:

• a) provision of a support material having chelate ligands based on silica
• b) activation of the support material from step a) using transition-metal ions, oxides or oxide hydrates of transition-metal ions or trivalent ions of metals from the third main group
• c) bringing a phosphopeptide-containing sample into contact with the activated support material in the presence of a binding buffer
• d) removal of the supernatant consisting of the binding buffer and the unbound part of the sample
• e) optionally washing of the support material
• f) elution of the phosphopeptides with an elution buffer which has a pH>10 and comprises alkali metal, alkaline earth metal or ammonium salts of thiocyanate, of acids of the complex ligands nitrito, isocyano, nitrile, isocyanato, isothiocyanato, azido, ethylenediamine, isonitrile, fulminato and cyano and/or of the oxygen acids of phosphorus, sulfur, vanadium, ruthenium, niobium, tantalum, tungsten or of molybdenum, and/or chelating agents.