Detection of translocation events using graphene-based nanopore assemblies

Abstract

Translocation events are sensed using composite nanopore assemblies including nanopores formed in graphene sheets. Single molecule detection and characterization and multi-molecule characterization and identification are provided using such assemblies. Multiple electrodes associated with nanofluidic sensors facilitate detection of ionic current through a nanopore as well as tunneling currents. Current signals of individual molecules are estimated from the combination of an ionic current signal through the nanopore and tunneling current signals obtained at specific locations within the nanopore.

1 - 20 . (canceled) 
     
     
         21 . A nanopore assembly for detecting translocation of charged molecules, comprising:
 a solid state membrane, the solid state membrane including a plurality of first nanopores extending therethrough;   a plurality of graphene layers in alternating sequence with and electrically isolated by the solid state membrane, each of the plurality of graphene layers including a plurality of discrete graphene strips, each of the discrete graphene strips including a plurality of second nanopores extending therethrough, the second nanopores extending through each discrete graphene strip being coaxially aligned, respectively, with a plurality of the first nanopores and a plurality of the second nanopores extending through another one of the discrete graphene strips.   
     
     
         22 . The nanopore assembly of  claim 21 , wherein the discrete graphene strips comprising a first of the graphene layers have longitudinal axes that extend in a first direction and the discrete graphene strips comprising a second of the graphene layers have longitudinal axes that extend in a second direction intersecting the first direction, one or more of the discrete graphene strips comprising the first graphene layer overlapping one or more of the discrete graphene strips comprising the second graphene layer. 
     
     
         23 . The nanopore assembly of  claim 22 , wherein one or more of the discrete graphene strips comprising the first of the graphene layers overlap at least two of the discrete graphene strips comprising the second of the graphene layers. 
     
     
         24 . The nanopore assembly of  claim 23 , wherein the discrete graphene strips comprising the first of the graphene layers extend perpendicularly with respect to the discrete graphene strips comprising the second of the graphene layers. 
     
     
         25 . The nanopore assembly of  claim 24 , wherein the discrete graphene strips comprising the first of the graphene layers are parallel to each other and the discrete graphene strips comprising the second of the graphene layers are parallel to each other. 
     
     
         26 . The nanopore assembly of  claim 24 , wherein the first and second graphene layers are separated by five to ten nanometers. 
     
     
         27 . The nanopore assembly of  claim 24 , further including one or more detectors for detecting tunneling currents, the one or more detectors being electrically connected to the discrete graphene strips. 
     
     
         28 . The nanopore assembly of  claim 21 , further including additional solid state membranes in alternating sequence with the plurality of graphene layers, each of the additional solid state membranes including third nanopores extending therethrough and coaxially aligned, respectively, with a plurality of the first nanopores and a plurality of the second nanopores. 
     
     
         29 . The nanopore assembly of  claim 28 , further including one or more detectors for detecting tunneling currents, the one or more detectors being electrically connected to the discrete graphene strips. 
     
     
         30 . The nanopore assembly of  claim 21 , wherein the solid state membrane is a Si x N y  membrane. 
     
     
         31 . The nanopore assembly of  claim 21 , wherein the discrete graphene strips within each graphene layer are parallel to each other. 
     
     
         32 . The nanopore assembly of  claim 31 , wherein the discrete graphene strips have rectangular configurations. 
     
     
         33 . The nanopore assembly of  claim 21 , wherein the discrete graphene strips extend beyond a peripheral edge of the solid state membrane.