Presentation Information
[1P52]Interfacial structure of self-assembled peptides on two-dimensional materials for biosensing applications
*Niina Uenodan1, Yuhei Hayamizu2, Yoichi Yamada1 (1. Graduate School of Science and Technology, University of Tsukuba, 2. School of Materials and Chemical Technology, Institute of Science Tokyo)
Self-assembling peptides are attracting increasing attention for functionalizing two-dimensional materials such as graphene and MoS₂ in transistor-based biosensors, due to their high affinity for biomolecules and versatile sequence designs. We investigated the interfacial structures and surface properties of self-assembled monolayers of a histidine-repeat dipeptide, YH₄ (YHYHYHYH), on highly oriented pyrolytic graphite (HOPG) and MoS₂. The films were prepared by immersing substrates in aqueous peptide solution under controlled temperature, followed by rinsing, drying, and desiccation. Atomic force microscopy showed that YH₄ formed films oriented to the hexagonal symmetry of the substrates, with β-sheet bundles on MoS₂ and uniform β-sheet domains on HOPG. Ultraviolet photoelectron spectroscopy revealed a 0.1 eV increase in work function on HOPG and a 0.3 eV decrease on MoS₂, indicating opposite dipole orientations. These results provide insight into controlling peptide alignment and tuning sensing performance in peptide-functionalized 2D devices.