Abstract: A solid-state nanopore system includes a single-molecule chip that works on the principle of pore occlusion by the detected molecule, which then can be registered as a change in ionic current. Low-noise and low-capacitance glass chips are used with ultrathin (<20 nm) silicon nitride (SiN) nanopores of 1.5-5 nm diameter and a miniaturized nanopore reader are used as the nanopore sensor, which is capable of sensing the presence of mercury ion (Hg2+) and lead ion (Pb2+) at concentrations down to 0.5 nM and 5 nM, respectively. Detectable distinct electrical translocation characteristics between the two metal ions were enabled by short DNA molecules (aptamers) functioning as a carrier, binding via specific interactions with the metal ions to provide a selective nanopore sensor for water monitoring by identification of electrical fingerprints of the respective ions.

Abstract: Ultra-low noise nanopore chips with ultra-high signal are produced at the wafer scale by combining fused-silica chips that have ultra-low capacitance (which dominates signal noise at high bandwidth) with local ultra-thin regions. The method uses electron-beam lithography (EBL) and hydrofluoric acid (HF) etching is applied to the fused-silica chips in a manner designed to avoid labor intense thinning techniques and to ensure reproducible thickness of the membrane while maintaining the robust character of the resulting nanopore chips. The resulting nanopore chips are used to detect small organic analytes (˜1 nm), such as diethyl phthalate (DEP), that are desirable to measure for water monitoring applications such as in the water system aboard the International Space Station (ISS) and other spacecraft.

Abstract: A solid-state nanopore system includes a single-molecule chip that works on the principle of pore occlusion by the detected molecule, which then can be registered as a change in ionic current. Low-noise and low-capacitance glass chips are used with ultrathin (<20 nm) silicon nitride (SiN) nanopores of 1.5-5 nm diameter and a miniaturized nanopore reader are used as the nanopore sensor, which is capable of sensing the presence of mercury ion (Hg2+) and lead ion (Pb2+) at concentrations down to 0.5 nM and 5 nM, respectively. Detectable distinct electrical translocation characteristics between the two metal ions were enabled by short DNA molecules (aptamers) functioning as a carrier, binding via specific interactions with the metal ions to provide a selective nanopore sensor for water monitoring by identification of electrical fingerprints of the respective ions.