Protein reversible combination with cations

Serum albumin, in addition to its important osmotic function, shows specific powers of reversible combination with a large variety of molecules. These include the anions and cations of many acid and basic dyes the anions of fatty acids and alkyl sulfonic acids, of many aromatic carboxylic acids and acetylated amino acids sulfonamide derivatives many types of naphthoquinone derivatives and a variety of other compounds. All these substances show a very strong preferential tendency to combine with albumin, rather than with the other proteins of... 

In the gel-free approaches, also referred as shotgun proteomics, proteins in a mixture are digested and the peptides released separated by reverse-phase HPLC, either alone or combined with strong cation exchange chromatography... 

Size exclusion, reversed-phase, paired ion reverse-phase, and ion exchange (cation and anion) HPLC have been used for selenium speciation. Size exclusion, also used in combination with affinity chromatography, has been used for the determination of selenoproteins and studies of interactions of selenium with proteins in the body. Ion-exchange and reversed-phase HPLC are often used for separation... 

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