N-laurylbiotinamide as affinity surfactant

N-laurylbiotinamide (NLB), which retains strong affinity for the protein avidin, was synthesized from biotin and N-laurylamine via the biotin ester of N-hydroxysuccinimide and characterized by NMR. When the synthesized NLB was used as a cosurfactant with AOT to form a reverse micellar system in isooctane, it was found to extend the pH range over which avidin can be transferred from a continuous aqueous solution to the reverse-micellar phase. This behavior is similar to that already reported for a different affinity surfactant, n-octyl beta-D-glucopyranoside.