Biochemical Techniques and Instrumentation

2.4.2.1. Organic supports

They are supports made of biological materials such as cellulose, dextran and agarose.

1. Cellulose: Cellulose was the first material used for attachment of affinity ligands mainly for the isolation of enzymes. They do not promote fast flow rates, but are chemically inert and cheap.

2. Dextran: Dextran is a microbial polysaccharide. They are cross-linked with epichlorohydrin to produce a beaded gel. They are highly hydrophilic due to OH groups, which are used to attach ligand.

3. Agarose: Agarose is the most popular material used as an affinity support. They produce hydrophilic beads. The major disadvantage is that they have a tendency to nonspecifically bind proteins and nucleic acids. eg. Sepharose and Superose 6B