Send to

Choose Destination
Sens Actuators B Chem. 2013 Feb 1;177:1075-1082.

Detecting single-abasic residues within a DNA strand immobilized in a biological nanopore using an integrated CMOS sensor.

Author information

Department of Computer Engineering, University of California at Santa Cruz, Santa Cruz, CA 95064, U.S.A.
Department of Electrical Engineering, University of California at Santa Cruz, Santa Cruz, CA 95064, U.S.A.


In this paper, we demonstrate the application of a novel current-measuring sensor (CMS) customized for nanopore applications. The low-noise CMS is fabricated in a 0.35μm CMOS process and is implemented in experiments involving DNA captured in an α-hemolysin (α-HL) nanopore. Specifically, the CMS is used to build a current amplitude map as a function of varying positions of a single-abasic residue within a homopolymer cytosine single-stranded DNA (ssDNA) that is captured and held in the pore. Each ssDNA is immobilized using a biotin-streptavidin linkage. Five different DNA templates are measured and compared: one all-cytosine ssDNA, and four with a single-abasic residue substitution that resides in or near the ~1.5nm aperture of the α-HL channel when the strand is immobilized. The CMOS CMS is shown to resolves the ~5Å displacements of the abasic residue within the varying templates. The demonstration represents an advance in application-specific circuitry that is optimized for small-footprint nanopore applications, including genomic sequencing.


Biomedical instrumentation; CMOS current-measuring sensor; DNA-binding proteins; gene sequencer; nanopore technology; potentiostat; single-molecule science

Supplemental Content

Full text links

Icon for PubMed Central
Loading ...
Support Center