A fusion protein for regenerative surfaces

Immobilization of biomolecules on solid surfaces is often combined with a partial loss of functionality. Therefore, smooth immobilization procedures are urgently required. Most recently, a Concanavalin A–Streptavidin (Con A–SAv) fusion protein was obtained, which allows the design of functionalized interfaces via self‐assembling. The protein was successfully produced in Escherichia coli and the functionality was tested by surface plasmon resonance (SPR) measurements as well as by the mean of reflectometric interference spectroscopy. A re‐generation of the mannan‐coated surfaces, by washing with buffer containing 10% methyl α‐D‐mannopyranoside, could be demonstrated. This procedure should allow multiple measurements without replacing the chip. Investigation of the functionalized surfaces by atomic force microscopy showed a rather uniform coating with mannan and the fusion protein. In conclusion, the designed Con A–SAv fusion protein can be used as a universal linker between mannan‐coated surfaces and biotinylated biomolecules, e.g. biotinylated antibodies.