Nanopipette Electrochemistry

Nanopipette electrochemistry has emerged as a versatile platform for nanoscale analytical measurements, functional device fabrication, and biomimetic interface construction. The confined geometry at the nanopipette orifice can be a powerful tool for ultrasensitive measurement through analyzing the ionic current across the nanopore. Chemists can rationally engineer the surface properties of nanopipettes by modifying the glass orifice through physical deposition or chemical reactions, enabling dynamic tuning of ion transport based on the interaction between the analyte and the interface. Such interfacial modulation governs the ionic flux and provides insights into local molecular processes. We first discuss ion current rectification (ICR) sensing, which enables surface-state probing via asymmetric ionic flux. Facilitated by the development of low-noise, high-bandwidth instruments, label-free and high-throughput detection and characterization of nanoparticles, single molecules, and real-time biological interactions could be achieved through resistive-pulse sensing. Furthermore, we highlight the role of wireless nanopore electrodes (WNEs) in studying electron transfer processes at the single-entity level, including redox processes in molecules, nanomaterials, and cellular metabolism. Nanopipettes also offer precise spatial control for the bottom-up electrochemical construction of functional nanostructures. Looking ahead, the integration of nanopipette arrays, hybrid analytical techniques, and adaptive interfaces and nanopipette electrochemistry is expected to enable the development of intelligent ionic circuits, neuromorphic systems, and next-generation molecular-scale computing platforms.