Biosensor membranes

• US 5,798,030 A
• Filed: 04/09/1997
• Issued: 08/25/1998
• Est. Priority Date: 05/17/1995
• Status: Expired due to Fees

• Current Assignee: Biosensor Enterprises, LLC
• Original Assignee: Australian Membrane and Biotechnology Research Institute, University of Sydney
• Inventors: Raguse, Burkhard, Pace, Ronald J, Cornell, Bruce A, Braach-Maksvytis, Vijoleta L
• Primary Examiner(s): Bell, Bruce F.
• Application Number:
  US08/826,904
• Time in Patent Office: 503 Days
• Field of Search: 204/415, 204/418, 204/403, 435/287.1, 435/289.1, 435/817
• US Class Current: 204/403.08
• CPC Class Codes: C12Q 1/001 Enzyme electrodes
• CPC Class Codes: G01N 27/3275 Sensing specific biomolecules, e.g. nucleic acid strands, based on an electrode surface reaction
• CPC Class Codes: Y10S 435/817 Enzyme or microbe electrode

Abstract

The present invention relates to a novel biosensor comprising an electrode membrane combination. This novel biosensor employs compounds include a linker lipid for use in attaching a membrane including a plurality of ionophores to an electrode and providing a space between the membrane and the electrode, the electrode being either in part or totally made up of the linker lipid. The linker lipid comprises within the same molecule a hydrophobic region capable of spanning the membrane, an attachment group used to attach the molecule to an electrode surface, a hydrophilic region intermediate said hydrophobic region and the attachment group and a polar head group region attached to the hydrophobic region at a site remote from the hydrophilic region.

Claims

1. A biosensor for use in detecting the presence or absence of an analyte in a sample, the biosensor comprising an electrode and a bilayer membrane comprising a top layer and a bottom layer, the bottom layer being proximal to and connected to the electrode such that a space exists between the membrane and the electrode, the conductance of the membrane being dependent on the presence or absence of the analyte, the membrane comprising a closely packed array of amphiphilic molecules and a plurality of ionophores dispersed therein, and a layer of a hydrogel formed on top of the lipid bilayer membrane, the hydrogel allowing the passage of the analyte molecule to be detected.

2. A biosensor as claimed in claim 1 in which the hydrogel is a thermosetting gel.

3. A biosensor as claimed in claim 2 in which the thermosetting gel is an agar gel.

4. A biosensor as claimed in claim 2 in which the gel contains between 0.3-5% agar.

5. A biosensor as claimed in claim 2 in which the thermosetting gel is a gelatine gel.

6. A biosensor as claimed in claim 1 in which the hydrogel is an in situ polymerised hydrogel.

7. A biosensor as claimed in claim 1 in which the hydrogel is an acrylic acid or an acrylic acid derivative that is polymerised by free radial polymerisation.

8. A biosensor as claimed in claim 1 in which the hydrogel is formed from acrylamide and a bisacrylamide cross-linker.

9. A biosensor as claimed in claim 1 in which the hydrogel is formed from cross-linked hydroxyethyl acrylate or hydroxyethyl methacrylate or other biocompatible gel.

10. A biosensor as claimed in claim 1 in which the ionophore is capable of transporting an ion that is produced by the reaction of an enzyme with its substrate, said enzyme being either covalently or non-covalently attached to the hydrogel.