METHOD AND APPARATUS FOR TARGET DETECTION USING ELECTRODE-BOUND VIRUSES

• US 20140014536A1
• Filed: 07/12/2013
• Published: 01/16/2014
• Est. Priority Date: 03/09/2006
• Status: Active Grant

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Weiss, Gregory A., Penner, Reginald M., Tam, Phillip Y., Yang, Li-Mei, Brigham, Tyler
• Granted Patent: US 9,316,608 B2
• Time in Patent Office: Days
• US Class Current: 205/792
• CPC Class Codes: G01N 27/327 Biochemical electrodes , e.g. electrical or mechanical details for in vitro measurements
• CPC Class Codes: G01N 27/3277 being a redox reaction, e.g. detection by cyclic voltammetry voltammetry per se G01N27/42, G01N27/48

Abstract

A biosensor that is capable of detecting the presence and/or concentration of an analyte or biomarker includes at least one electrically conductive electrode operatively coupled to an impedance analyzer for measuring the change in the resistive impedance ΔZ_Re of the electrode in response to an applied alternating current at a plurality of frequencies. In one embodiment, at least one electrode is covered with a self-assembled monolayer that is chemically bonded to a surface. A plurality of virus particles such as phage viruses are immobilized on the self-assembled monolayer and may be exposed to a test or sample solution. The virus particles may be obtained from phage-displayed libraries to detect a wide variety of targets including, for example, DNA, RNA, small molecules, and proteins or polypeptides. In another embodiment, the virus particles are electrostatically bound to a substrate in between a pair of elongated electrodes disposed on a substrate.

Claims

1. A biosensor comprising:

an electrically conductive electrode operatively coupled to an impedance analyzer for measuring the change in the resistive impedance Δ

Z_Re of the electrode;

a self-assembled monolayer chemically bonded to a surface of the electrically conductive electrode; and

a plurality of virus particles covalently bound to the self-assembled monolayer.

53. The biosensor of claim 1, further comprising one or more macromolecules disposed in the self-assembled monolayer.

54. The biosensor of claim 53, wherein the macromolecule comprises bovine serum albumin (BSA) disposed in the self-assembled monolayer.

55. The biosensor of claim 1, wherein the plurality of virus particles comprise phage particles.

56. The biosensor of claim 55, wherein the plurality of phage particles comprise bacteriophage M13.

57. The biosensor of claim 55, wherein the plurality of phage particles selectively bind to prostate specific membrane antigen (PSMA).

58. The biosensor of claim 1, further comprising a processor operatively connected to the impedance analyzer for calculating an analyte concentration based at least in part on the measured change in resistive impedance Δ

Z_Re

59. The biosensor of claim 1, wherein the self-assembled monolayer comprises N-hydroxysuccinimide thioctic ester.

60. The biosensor of claim 1, wherein substantially the entire self-assembled monolayer is pinhole free.

61. The biosensor of claim 1, wherein the impedance analyzer is operatively coupled to the electrically conductive electrode so as to apply an alternating current within the frequency range of about 2 kHz to about 500 kHz.

2-52. -52. (canceled)

62. A method of detecting an analyte in a test solution comprising:

providing a biosensor comprising at least one electrically conductive electrode, a self-assembled monolayer bonded to the electrically conductive electrode, and a plurality of virus particles chemically bound to the self-assembled monolayer;

coupling the at least one electrically conductive electrode to an impedance measurement device;

exposing the biosensor to the test solution;

measuring the change in the resistive impedance Δ

Z_Re of the at least one electrically conductive electrode; and

detecting the presence of the analyte based at least in part on the measured change in resistive impedance Δ

Z_Re of the at least one electrically conductive electrode, the change in resistive impedance Δ

Z_Re comprising taking the difference of the measured resistive impedance Z_Re of the at least one electrically conductive electrode when bound to the analyte and not bound to the analyte.

63. The method of claim 62, further comprising determining the concentration of the analyte based at least in part on a comparison of the measured change in the resistive impedance Δ

Z_Re of the at least one electrically conductive electrode and a calibration curve.

64. The method of claim 62, wherein the analyte comprises an antibody.

65. The method of claim 62, wherein the analyte comprises prostate specific membrane antigen (PSMA).

66. The method of claim 62, wherein the analyte is selected from the group consisting of an organic species, an inorganic species, and a biomolecule.

67. The method of claim 62, wherein the impedance measurement device applies is operatively connected to the at least one electrically conductive electrode to measure impedance at a supplied alternating current within a frequency range of about 2 kHz to about 500 kHz.

68. A system for detecting the presence of an analyte in a sample comprising:

an electrically conductive electrode operatively coupled to an impedance analyzer for measuring the change in the resistive impedance Δ

Z_Re of the electrode in response to an applied alternating current;

a self-assembled monolayer chemically bonded to a surface of the electrically conductive electrode;

a plurality of virus particles covalently bound to the self-assembled monolayer; and

at least one processor operatively coupled to the impedance analyzer for comparing the change in the measured resistive impedance Δ

Z_Re with one or more pre-set values, the at least one processor configured for outputting a signal indicative of analyte detection based at least in part on the comparison.

69. The system of claim 68, wherein the electrically conductive electrode is disposed in a flow cell.

70. The system of claim 68, wherein the at least one processor is configured for outputting a signal indicative of the analyte concentration based at least in part on the comparison.

71. The system of claim 68, wherein the electrically conductive electrode comprises an array of electrodes.

72. The system of claim 68, wherein the electrically conductive electrode is disposed in a probe.

73-80. -80. (canceled)