Simple Fractionations Employing Highly Cross-Linked Gels

Simple Fractionations Employing Highly Cross-Linked Gels 

Separation of Salts and Other Small Molecular Size Solutes from Proteins and Peptides 

In 1954 Deuel and Neukom briefly pointed out that beds of granulated cross-linked locust bean gum could be used to separate salts from high-molecular weight solutes (this fact was unknown to Dr. Flodin and me until 1961 when Professor Deuel kindly informed us of it). Desalting of proteins was one of the first applications of Sephadex (Porath and Flodin, 1959). Distilled water was first used as a developer for the serum proteins 

Sephadex is particularly useful for buffer exchange. When exhaustive removal of salts is required Sephadex may be used in a two-step procedure. The original buffer is exchanged for a volatile buffer system and the latter is subsequently removed by lyophilization. 

Gel filtration compares very favorably with dialysis through membranes (Kisliuk, 1960). It is rapid and can be performed on either a micro- or a macroscale. The desalting of virus by this procedure has been reported by Matheka and Wittmann (1961). 

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III. Simple Fractionations Employing Highly Cross-Linked Gels. 211... 

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