Docking of a Second Functional Protein Layer to a Streptavidin Matrix on a Solid Support: Studies with a Quartz Crystal Microbalance

A long, flexible, hydrophilic spacer is needed in the biotinlipid for the specific binding of the protein streptavidin to the lipid‐containing membrane. This was shown by measurements with a quartz crystal microbalance, which indicated that 1 was specifically binding. The binding of a second protein layer of biotinylated Fab fragment to the streptavidin matrix could also be monitored in real time by this method.