Electric Field-Controlled Peptide Self-Assembly through Funnel-Shaped Two-Dimensional Nanopores

Self-assembly
of biomolecules is critical for the realization
of
biological functions. Thus, the precise control of self-assembly has
great significance in the design of biochips and biomedical agents.
In this report, we design a Y-shaped funnel on a two-dimensional (2D)
heterostructure, called 2D funnel, based on monolayered polyaniline
carbon nitride (C3N) and boron carbide (BC3),
and study its application in the self-assembly state regulation of
the peptide oligomer, using Aβ16–21 as the
representative model. Structurally, the 2D funnel is composed of three
regions: channel area, triangle area, and barrier area. The channel
and triangle areas show higher binding affinity to the peptide than
that of the barrier area, which leads to the confinement of the peptide
in the 2D funnel. Our results show that when an external electric
field is applied along the 2D funnel, the oligomer is driven to migrate
across the funnel. Its trajectory is confined inside the narrow channel
area, which effectively causes peptide dissociation into the individual
peptide chains. Then, when the external electric field is turned off,
the separated peptide chains spontaneously assemble in the triangle
area and tend to reunite. Our present findings propose a novel heterostructure
platform, which enables the manipulation of the self-assembly state
of peptides by switching the electric field, which could guide the
design and fabrication of nanodevices for sensing and sequencing applications.