Recombinant streptavidin isolated from Streptomyces avidinii is immobilized on high-crossed linked 6% agarose beads. Streptavidin Beads 6FF can be used to bind biotin and biotinylated substances. The interaction between streptavidin and biotin is very strong and requires denaturating conditions for elution, which may destroy both the ligand and the sample. The interaction between 2-iminobiotin and streptavidin is weak, it can be eluted at pH4.0, which preserve the biomolecules activity. The crosslinking of the base matrix has been optimized to give the matrix good flow properties and high physical and chemical stability, both of which are key factors for cost-effective, large-scale use.