Peptide-Induced Synthesis of Graphene-Supported Au/Pt Bimetallic Nanoparticles for Electrochemical Biosensor Application

Understanding the self-assembly behavior of peptides is crucial for the design and synthesis of functional peptide-based nanomaterials for various applications. In this study, a bifunctional peptide molecule with a sequence of KIIIIKYWYAF is designed, which reveals multiple functions for self-assembling formation of peptide nanofibers (PNFs), noncovalent graphene oxide (GO) binding, and biomimetic metallization of nanoparticles (NPs). Well-defined PNFs are obtained through the optimization of experimental conditions, which are further utilized to bind with GO to form GO/PNF nanohybrids via noncovalent interactions. Ascribed to the biomimetic function of peptide molecules, bimetallic gold-platinum NPs (Au-Pt NPs) are created along the PNFs by metallic ion adsorption and subsequent chemical reduction. The synthesized GO/PNF/Au-Pt nanohybrids reveal improved electrochemical activity compared to Au, Pt, and Au-Pt NPs, indicating potential contributions of both GO and PNFs to the final electrochemical sensing performance of the GO/PNF/Au-Pt-based electrodes. The fabricated electrochemical non-enzymatic biosensors exhibit a detection limit of 0.379 mu m and linear detection ranges of 1 mu m-1 mm and 1-20 mm. The current study provides a facile strategy for the creation of peptide-based superstructures with multiple functions and will inspire the design and synthesis of graphene-peptide based nanomaterials for biomedicine, tissue engineering, and bioanalysis applications.

Automated summary

In this study, a bifunctional peptide molecule was designed to self-assemble into peptide nanofibers and bind with graphene oxide to form nanohybrids. Biomimetic gold-platinum nanoparticles were synthesized along the peptide nanofibers. The resulting nanohybrids showed improved electrochemical activity and potential applications in biosensors.