Fibroin-like peptides self-assembling on two-dimensional materials as a molecular scaffold for potential biosensing

Self-assembled peptides have revealed uniform ordering on two-dimensional (2D) materials such as mica, graphene, and MoS2 so far. These peptides are expected to be utilized as a molecular scaffold for biosensing based on 2D materials. However, the stability of the peptide structures on 2D materials under liquid has not been evaluated, and some of the previously reported peptides may have instability under water. In this work, by mimicking an amino-acid sequence of silk protein, we successfully developed peptide sequences that can maintain ordered nanostructures even after rinsing with DI water. The structural stability was also proven under electrochemical bias, which is crucial as a biomolecular scaffold for practical biosensing with 2D materials. The stability probably arises from its -sheet like structures with improved intermolecular interactions and binding to the surface of 2D materials, resulting in the formation of stable domains of ordered peptide structures. Our peptides showed its ability to i...