Glass nanopore-based ion-selective electrodes

Glass nanopore-based all-solid-state ion-selective electrodes (ISEs) have been developed to probe the distribution of ionic species at micro- or submicrometer-length scales, e.g., mapping of ion flux through micrometer-sized pores. The all-solid-state ISE was fabricated by sealing a conically etched platinum wire (d = 25-mu m; radius of etched tip < 10 nm) into a soda lime glass capillary. A Pt disk was exposed by gentle polishing the glass and the disk etched to form a conical pore of submicrometer dimension (radius