Affinity-based reversed micellar bovine serum albumin (BSA) extraction with unbound reactive dye

A quick and simple method has been introduced for affinity extraction with an unbound reactive dye in a reversed micellar system. Bovine serum albumin (BSA) and Cibacron Blue 3GA (CB) were chosen, respectively, as a model protein and an unbound ligand. CB in the aqueous phase was directly transferred to the reversed micelles due to electrostatic interaction between anionic CB and cationic cetyltrimethylammonium bromide. The BSA transfer to the reversed micelles increases significantly by affinity interaction with the addition of a small amount of CB to the aqueous phase. For solutions with pH close to pI, the selectivity of proteins can be expected in the presence of affinity CB as very little BSA is extracted into the reverse micelles without the addition of CB. Most of the BSA (similar to 82%) extracted into the reversed micelles can be backextracted into the stripping aqueous phase by increasing of n-hexanol concentration in the organic phase while no CB is transferred to the aqueous solution at the same time.