Abstract Mimicking the molecular recognition functionality of antibodies is a great
challenge. Foldamers are attractive candidates because of their relatively small size
and designable interaction surface. This paper describes a sandwich type enzyme-linked
immunoassay with a tetravalent β-peptide foldamer helix array as capture element and
enzyme labeled tracer antibodies. The assay was found to be selective to β-amyloid
oligomeric species with surface features transiently present in ongoing aggregation.
In optimized conditions, with special emphasis on the foldamer immobilization, a detection
limit of 5 pM was achieved with a linear range of 10–500 pM. These results suggest
that protein mimetic foldamers can be useful tools in biosensors and affinity assays.