Method and device for high sensitivity detection of the presence of DNA and other probes

• US 7,943,394 B2
• Filed: 06/24/2003
• Issued: 05/17/2011
• Est. Priority Date: 06/24/2002
• Status: Expired due to Fees

• Current Assignee: Université catholique de Louvain
• Original Assignee: Université catholique de Louvain
• Inventors: Remacle, José, Hagelsieb, Luis Moreno, Pampin, Rémi, Flandre, Denis, Bourgeois, David, Lobert, Pierre-Emmannuel
• Primary Examiner(s): Bullock; In Suk
• Assistant Examiner(s): Kingan; Timothy G
• Application Number:
  US10/519,014
• Publication Number:
  US 20050227373A1
• Time in Patent Office: 2,884 Days
• Field of Search: 436/501, 436/63, 436/98, 436/104, 436/111, 422/82.01
• US Class Current: 436/501
• CPC Class Codes: G01N 27/221 by investigating the dielectric properties using microwaves G01N22/00; measuring loss factors or dielectric constants per se G01R27/26
• CPC Class Codes: G01N 27/226 Construction of measuring vessels; Electrodes therefor
• CPC Class Codes: G01N 33/5438 Electrodes
• CPC Class Codes: Y10T 436/147777 Plural nitrogen in the same ring [e.g., barbituates, creatinine, etc.]
• CPC Class Codes: Y10T 436/163333 Organic [e.g., chemical warfare agents, insecticides, etc.]
• CPC Class Codes: Y10T 436/173845 Amine and quaternary ammonium

Abstract

The present invention provides a method for capacitive detection of the presence of target sample on a substrate, which comprises the steps of: binding a target sample to selective binding sites on the substrate, the target sample being directly or indirectly labeled with conductive labels, and sensing the presence of the bound conductive labels to a binding site to thereby determine the presence of the target sample. The sensing step is carried out by a capacitive detection of the presence of the conductive labels. The present invention also provides a capacitive sensor device for determining the presence of a target sample. Conductive labels are directly or indirectly couplable to the target sample. The capacitive sensor device comprises a substrate having attached thereto a binding site able to selectively bind a target sample, a capacitive sensor element, and sensing circuitry for determining the presence of a target sample bound to the binding site by application of electrical signals to a capacitive sensor element. The capacitive sensor element comprises a set of at least two electrodes with non-conductive surfaces in a region associated with the binding site.

Claims

1. A method for capacitive detection of the presence of target sample on a substrate with at least a pair of electrodes having a non-conductive surface layer, comprising the steps of:

(a) binding a target sample to a selective binding site on the substrate, a conductive label being bound to the target sample, the conductive label having a direct or indirect coupling to the target sample; and

(b) sensing the presence of the bound conductive label to the binding site to thereby determine the presence of the target sample, wherein the sensing step is a capacitive detection that is carried out by contacting the conductive label bound to said target sample to said non-conductive surface layer of said pair of electrodes on said substrate.

2. A method according to claim 1, furthermore comprising, before the binding step, a preliminary capacitance measuring step.

3. A method according to claim 2, furthermore comprising a step of comparing the preliminary capacitance with the capacitance measured during the sensing step.

4. A method according to claim 1, wherein the labels are formed or enlarged prior to or during the sensing step.

5. A method according to claim 1, wherein capacitance is measured as function of frequency to obtain a value representative of an electrical resistive property of the conductive label.

6. A method according to claim 1, wherein a global impedance is measured and the real part of the global impedance is used in addition to the capacitive part.

7. A method according to claim 1, furthermore comprising a step of optical detection of the presence of the label.

8. A method according to claim 1, furthermore comprising a step of magnetic or radioactive emissions detection of the presence of the label.