Selective Binding of DNA Origami on Self-Assembled Monolayer-Patterned Gold Substrate

Abstract

DNA origami (DO) enables the precise spatial arrangement of guest components through sequence-specific hybridization. Its deterministic placement onto lithographically defined chemical patches-termed DO placement (DOP)-allows their integration into device architectures. However, conventional DOP has primarily been limited to oxide-based substrates, restricting its compatibility with broader device platforms. Herein, we demonstrate the selective binding of DO onto patterned gold (Au) substrates as a foundation for DOP on metallic substrates. Leveraging the versatility of microcontact printing of self-assembled monolayers (SAMs), we patterned Au substrates with regions of distinct surface potential energies. Initially, we employed monofunctionalized SAMs to explore the influence of surface chemistry and molecular density on DO binding. Monte Carlo simulations provided blueprints for the selective binding probability of DO as a function of the SAM composition and order-state. Guided by these insights, we then utilized bifunctionalized SAMs to achieve high-yield, site-selective DO binding on targeted regions of Au substrates.