Multifunctional Peptides Modified Conductive Nano-Network Based on GO and Gold Nano Triangular: Sensitive Detection of PD-L1 Exosomes in Serum

Abstract

Early diagnosis and reasonable treatment of cancer can effectively reduce the progression and decrease the proliferation. Exosomes are considered to be an excellent biomarker due to their special role in cancer development and post-treatment evaluation. Here, a simple and effective method for constructing two-dimensional heterostructure modified films on the electrode surface is reported to realize the electrochemical detection of exosomes. Flake gold nano triangle (AuNTs) as spacer, effectively inhibits the decline of electron transport capacity caused by the van der Waals stacking effect of graphene, a layered conductive network based on GO/AuNTs heterojunction was constructed on glassy carbon electrode. Multifunctional peptides with antifouling and specific binding characteristics for target exosomes were carefully anchored onto the surface of GO/AuNTs conductive network composite through Au-S. Combined with the innovative micro nanostructure on the electrode surface and the multifunctional peptides probe, the fabricated sensor shows an excellent limit of detection of 76 particles/ml with a detection range of 102 to 106 particles ml−1. The proposed sensor provides a powerful platform for direct measurement of exosomes, opening new opportunities for highly sensitive determination of other biomarkers.