A new type of reusable piezoimmunosensor fabricated by a recombinant IgG-binding protein

Abstract

A reusable immunosensor was developed with the self-assembly of a recombinant antibody-binding protein on the gold electrode of a quartz piezoelectric crystal as the antibody receptor. The recombinant protein, B5C1, was genetically produced by introducing a cysteine residue at the C-terminus of 5 B-domains of protein A. Its self-assembling properties were studied using piezoelectric quartz crystals. The B5C1 assembled crystal showed higher antibody- binding activity and was more stable than that of the native protein A coated crystal. One B5C1 assembled crystal can be used repeatedly at least 30 times without detectable loss of antibody-binding activity.