We reported a general way to design electrochemical biosensor with a peptide probe.

The probe acts as the receptor of target and the inducer of nanoparticles aggregation.

Colorimetric assay was converted into electrochemical assay with improving sensitivity.

Human chorionic gonadotropin and amyloid-β oligomer were tested as model analytes.

It is helpful for design of new electrochemical sensors by marrying specific probes.