SPECIFIC RECOGNITION-INDUCED SELF-ASSEMBLY OF A BIOTIN LIPID STREPTAVIDIN FAB FRAGMENT TRIPLE LAYER AT THE AIR-WATER-INTERFACE - ELLIPSOMETRIC AND FLUORESCENCE MICROSCOPY INVESTIGATIONS

Self-assembled biotin lipid/streptavidin/Fab triple layers at the air/water interface were investigated by ellipsometry and fluorescence microscopy. The triple layer was prepared by spreading a biotin lipid monolayer at the air/water interface and then by sequentially injecting solutions of first streptavidin and then biotinylated Fab into the subphase. Between the injections the subphase was flushed with pure buffer. The preparation method was designed to promote the formation of a close-packed monolayer of confluent streptavidin (crystalline) domains which served as a template for Fab binding. Ellipsometric measurements indicated a dense attachment of the biotinylated Fab to this streptavidin template through a specific interaction with the streptavidin binding sites.