WO1999049307A1 - Sensor with improved shelf life - Google Patents

Sensor with improved shelf life Download PDF

Info

Publication number
WO1999049307A1
WO1999049307A1 PCT/AU1999/000166 AU9900166W WO9949307A1 WO 1999049307 A1 WO1999049307 A1 WO 1999049307A1 AU 9900166 W AU9900166 W AU 9900166W WO 9949307 A1 WO9949307 A1 WO 9949307A1
Authority
WO
WIPO (PCT)
Prior art keywords
metal electrode
coating
sulfur containing
containing moiety
group
Prior art date
Application number
PCT/AU1999/000166
Other languages
French (fr)
Inventor
Alastair Mcindoe Hodges
Ronald Christopher Chatelier
Original Assignee
Usf Filtration And Separations Group Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Usf Filtration And Separations Group Inc. filed Critical Usf Filtration And Separations Group Inc.
Priority to JP2000538226A priority Critical patent/JP2002507744A/en
Priority to AU29136/99A priority patent/AU745414B2/en
Priority to CA002322454A priority patent/CA2322454C/en
Priority to EP99910013A priority patent/EP1084397A4/en
Publication of WO1999049307A1 publication Critical patent/WO1999049307A1/en
Priority to US09/664,688 priority patent/US6652734B1/en
Priority to US10/630,441 priority patent/US7335292B2/en
Priority to US11/926,369 priority patent/US20080121533A1/en

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
    • G01N27/28—Electrolytic cell components
    • G01N27/30—Electrodes, e.g. test electrodes; Half-cells
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
    • G01N27/28—Electrolytic cell components
    • G01N27/30—Electrodes, e.g. test electrodes; Half-cells
    • G01N27/327—Biochemical electrodes, e.g. electrical or mechanical details for in vitro measurements
    • G01N27/3271—Amperometric enzyme electrodes for analytes in body fluids, e.g. glucose in blood

Definitions

  • the invention relates to apparatus comprising one or more metal electrodes such as electrochemical cells, sensor elements and the like, and more particularly to extending the l o shelf life of such apparatus.
  • Metal electrodes have proved useful in sensor elements for sensing a diverse range of biologically important molecules eg glucose, and for determining physical properties such as pH.
  • a range of possible configurations and applications involving metal electrodes are 15 discussed in our co-pending applications PCT/AU96/00210, PCT/AU96/00365 and PCT/AU96/00723.
  • a desirable attribute of all sensor elements is that they have a long shelf life - that is, the sensing characteristic of the sensor element does not change significantly between manufacture and use (ie on storage).
  • the stability of the electrode is critical to the stability of the sensor as a whole.
  • electrodes When left to stand for long periods of time, electrodes become prone to instability in subsequent use thus limiting the useful shelf life. It is thought that such instability is caused by absorption or reaction of the metallic surface with atmospheric contaminants. It has also been observed that filling time of sensors 5 deteriorates on prolonged storage.
  • the invention consists in a metal electrode stabilised by a coating, the coating comprising a sulphur-containing moiety in its molecular structure. - 2 -
  • the sulphur-containing moiety is selected from the group comprising thiol, disulphide and SO x .
  • the sulphur-containing moiety is a disulphide.
  • the sulphur-containing moiety may also be incorporated in a cyclic structure.
  • the invention consists in a metal electrode stabilised by a coating according to the first aspect, further comprising a hydrophilic group in its molecular structure.
  • the hydrophilic group is selected from the group comprising hydroxyl, amine, carboxyl, carbonyl, oligo (ethylene oxide) chain, and zwitterionic species.
  • the hydrophilic group is a zwitterionic species. The most preferred zwitterionic species comprises an amine and a carboxyl group in proximity.
  • the invention consists in a metal electrode stabilised by a coating according to the second aspect, further comprising a spacer between the sulphur- containing moiety and the hydrophilic group.
  • the spacer consists of an alkyl group or an aromatic group. It is preferable that methylene or ethylene groups be included in the spacer element.
  • the invention consists in a method of preparing a metal electrode stabilised by a coating, comprising the step of contacting a metal electrode with a substance comprising a sulphur-containing moiety in its molecular structure.
  • the invention consists in a method of preparing a metal electrode stabilised by a coating, comprising the steps of contacting a metal electrode with a substance comprising a sulphur-containing moiety and a hydrophilic group in its molecular structure.
  • the invention consists in a method of preparing a metal electrode stabilised by a coating comprising the steps of contacting a metal electrode with a substance comprising a sulphur-containing moiety, a hydrophilic group and a spacer between the sulphur-containing moiety and the hydrophilic group in its molecular structure.
  • a substance comprising a sulphur-containing moiety, a hydrophilic group and a spacer between the sulphur-containing moiety and the hydrophilic group in its molecular structure.
  • the invention also consists in a method of sensing an analyte, comprising the step of substituting the electrode in a known sensor device with a metal electrode stabilised by a coating according to the present invention, and sensing an analyte.
  • thiols form coatings on metals.
  • Thiols have also been used to tether species such as antibodies onto metal surfaces, for instance those of gold particles, for the purposes of immobilisation etc.
  • tether species such as antibodies onto metal surfaces, for instance those of gold particles, for the purposes of immobilisation etc.
  • One would expect that such coatings would also bind contaminants to the surface.
  • the procedure for preparing the metal electrode stabilised by a coating involves contacting a metal electrode with selected sulphur-containing compounds, such as thiols, disulphides and compounds of the formula SO x among others being suitable in the context of the present invention.
  • the coatings also desirably contain a hydrophilic group which includes such species as hydroxyl, amino, carboxyl, carbonyl, oligo (ethylene oxide) chains and zwitterionic species. The latter two compounds indicate that compounds having one or more hydrophilic groups are also suitable groups for use in the present invention.
  • spacers may be employed between the sulphur group, which acts to tether the molecule onto the metal surface, and the hydrophilic group, which presents a hydrophilic surface.
  • Compounds useful in the present invention include, but are not limited to 2-mercapto ethanol, 2-mercaptoethylamine, 3-mercaptopropionic acid, thiophene, 4-carboxy thiophene, cysteine, homocysteine and cystine. Most preferably the molecule is cystine.
  • the D or L isomers can be used or mixtures of D and L isomers can be used, where such isomers are possible.
  • the compound in accordance with the invention is then applied as a monolayer or multilayer onto the surface of the electrode.
  • the compound it is possible to apply the compound by simply exposing the electrode to the coating material, with the coating material in either the vapour phase or in solution.
  • the substance can be applied by dipping, spraying, painting, printing etc. After application, it is possible to wash the surface of the contacted electrode.
  • the layer of the sulfur containing compound can optionally be overcoated with a surfactant layer.
  • the surfactant layer can be applied after the application of the sulfur containing layer or at the same time as the sulfur containing layer, for example the sulfur containing species and the surfactant can be placed in a coating bath into which the electrode material is immersed. Due to the higher affinity of the sulfur containing species for the electrode material it will bind to the electrode surface in preference to the surfactant, leaving the surfactant in a layer over the sulfur containing layer.
  • An example of a suitable surfactant is Triton X-100.
  • the electrode coatings were applied to gold or palladium electrodes by immersing the sheet of material from which the electrodes were made into a 1 mM aqueous solution of the coating compound adjusted to pH 12 by the addition of potassium hydroxide.
  • the contact time between the electrode material and the coating bath was typically 30 seconds.
  • the electrodes were washed by immersion in a bath of water. In some cases, the electrodes were immersed in a third bath containing 1,000 ppm of triton X-100 in water. Finally, the electrode material sheets were dried by blowing with air at room temperature.
  • the sensors were tested with whole blood samples with various glucose concentrations, from about 3 mM to 30 mM.
  • the background ferrocyanide concentration was measured (the reading obtained when a sample contains no glucose) and the overall precision and fill speed of the sensors was assessed.
  • the effect of the electrode coatings is shown in Table 1.
  • the fill speeds in Table 1 were assessed qualitatively by eye.
  • the fill speeds in Table 2 were assessed quantitatively by videoing the filling of the sensor with a blood sample using an on-screen timer and subsequently determining the number of seconds required for the blood to fill each sensor.
  • a desirable side effect of the present invention also appears to be maintenance of good fill speed for sensors on ageing.
  • Trit * saline rather than blood used to assess the background Trit denotes an overcoating of Triton X-100.

Abstract

The present invention provides a metal electrode stabilised by a coating, the coating comprising a sulfur containing moiety in its molecular structure. The coating may also include a hydrophilic group and a spacer between the sulfur containing moiety and the hydrophilic group. Preferably, the sulphur-containing moiety is selected from the group comprising thiol, disulphide and SOx, and the hydrophilic group is selected from the group comprising hydroxyl, amine, carboxyl, carbonyl, oligo (ethylene oxide) chain, and zwitterionic species. Compounds useful in the present invention include 2-mercaptoethanol, 2-mercaptoethylamine, 3-mercaptopropionic acid, thiophene, 4-carboxythiophene, cysteine, homocysteine, and cystine.

Description

- 1 -
SENSOR WITH IMPROVED SHELF LIFE
TECHNICAL FIELD
The invention relates to apparatus comprising one or more metal electrodes such as electrochemical cells, sensor elements and the like, and more particularly to extending the l o shelf life of such apparatus. BACKGROUND ART
Metal electrodes have proved useful in sensor elements for sensing a diverse range of biologically important molecules eg glucose, and for determining physical properties such as pH. A range of possible configurations and applications involving metal electrodes are 15 discussed in our co-pending applications PCT/AU96/00210, PCT/AU96/00365 and PCT/AU96/00723.
A desirable attribute of all sensor elements is that they have a long shelf life - that is, the sensing characteristic of the sensor element does not change significantly between manufacture and use (ie on storage). 0 In an electrochemical sensor element the stability of the electrode is critical to the stability of the sensor as a whole. Typically, when left to stand for long periods of time, electrodes become prone to instability in subsequent use thus limiting the useful shelf life. It is thought that such instability is caused by absorption or reaction of the metallic surface with atmospheric contaminants. It has also been observed that filling time of sensors 5 deteriorates on prolonged storage.
It is an object of the present invention to overcome or ameliorate at least some of the above disadvantages in the prior art.
Surprisingly, the present applicant has found that by coating a metal electrode with a monolayer or multilayer of selected materials, electrode behaviour can be significantly 30 stabilised in comparison with uncoated metal electrodes without loss of the desirable sensing characteristics of the electrodes. DESCRIPTION OF THE INVENTION
According to a first aspect, the invention consists in a metal electrode stabilised by a coating, the coating comprising a sulphur-containing moiety in its molecular structure. - 2 -
"Comprising" as herein used is used in an inclusive sense, that is to say in the sense of but not limited to "including" or "containing". The term is not intended in an exclusive sense ("consisting of or "composed of).
Preferably, the sulphur-containing moiety is selected from the group comprising thiol, disulphide and SOx. Most preferably the sulphur-containing moiety is a disulphide. The sulphur-containing moiety may also be incorporated in a cyclic structure.
According to a second aspect, the invention consists in a metal electrode stabilised by a coating according to the first aspect, further comprising a hydrophilic group in its molecular structure. Preferably, the hydrophilic group is selected from the group comprising hydroxyl, amine, carboxyl, carbonyl, oligo (ethylene oxide) chain, and zwitterionic species. Most preferably, the hydrophilic group is a zwitterionic species. The most preferred zwitterionic species comprises an amine and a carboxyl group in proximity.
According to a third aspect, the invention consists in a metal electrode stabilised by a coating according to the second aspect, further comprising a spacer between the sulphur- containing moiety and the hydrophilic group.
Preferably, in the third aspect, the spacer consists of an alkyl group or an aromatic group. It is preferable that methylene or ethylene groups be included in the spacer element.
According to a fourth aspect, the invention consists in a method of preparing a metal electrode stabilised by a coating, comprising the step of contacting a metal electrode with a substance comprising a sulphur-containing moiety in its molecular structure.
According to a fifth aspect, the invention consists in a method of preparing a metal electrode stabilised by a coating, comprising the steps of contacting a metal electrode with a substance comprising a sulphur-containing moiety and a hydrophilic group in its molecular structure.
According to a sixth aspect, the invention consists in a method of preparing a metal electrode stabilised by a coating comprising the steps of contacting a metal electrode with a substance comprising a sulphur-containing moiety, a hydrophilic group and a spacer between the sulphur-containing moiety and the hydrophilic group in its molecular structure. The preferred substances for use in the methods described in the fourth, fifth and sixth aspects are identical to those substances described in respect of the first, second and third aspects.
The invention also consists in a method of sensing an analyte, comprising the step of substituting the electrode in a known sensor device with a metal electrode stabilised by a coating according to the present invention, and sensing an analyte. BEST MODE FOR CARRYING OUT THE INVENTION
Various embodiments of the invention will now be described by way of example only. It is known in the prior art that thiols form coatings on metals. Thiols have also been used to tether species such as antibodies onto metal surfaces, for instance those of gold particles, for the purposes of immobilisation etc. One would expect that such coatings would also bind contaminants to the surface.
As much electrode chemistry involves interaction at the electrode surface, it is thus surprising that coatings used to bind molecules to the metal surface can be useful in preventing contamination of the electrode surface. It is also surprising that notwithstanding the application of the coating an electrode retains desirable electrochemical properties. The procedure for preparing the metal electrode stabilised by a coating involves contacting a metal electrode with selected sulphur-containing compounds, such as thiols, disulphides and compounds of the formula SOx among others being suitable in the context of the present invention. The coatings also desirably contain a hydrophilic group which includes such species as hydroxyl, amino, carboxyl, carbonyl, oligo (ethylene oxide) chains and zwitterionic species. The latter two compounds indicate that compounds having one or more hydrophilic groups are also suitable groups for use in the present invention.
Between the sulphur group, which acts to tether the molecule onto the metal surface, and the hydrophilic group, which presents a hydrophilic surface, spacers may be employed. Compounds useful in the present invention include, but are not limited to 2-mercapto ethanol, 2-mercaptoethylamine, 3-mercaptopropionic acid, thiophene, 4-carboxy thiophene, cysteine, homocysteine and cystine. Most preferably the molecule is cystine. In any of the above aspects, the D or L isomers can be used or mixtures of D and L isomers can be used, where such isomers are possible. The compound in accordance with the invention is then applied as a monolayer or multilayer onto the surface of the electrode. It is possible to apply the compound by simply exposing the electrode to the coating material, with the coating material in either the vapour phase or in solution. The substance can be applied by dipping, spraying, painting, printing etc. After application, it is possible to wash the surface of the contacted electrode.
In a further aspect of the current invention the layer of the sulfur containing compound can optionally be overcoated with a surfactant layer. The surfactant layer can be applied after the application of the sulfur containing layer or at the same time as the sulfur containing layer, for example the sulfur containing species and the surfactant can be placed in a coating bath into which the electrode material is immersed. Due to the higher affinity of the sulfur containing species for the electrode material it will bind to the electrode surface in preference to the surfactant, leaving the surfactant in a layer over the sulfur containing layer. An example of a suitable surfactant is Triton X-100. EXAMPLES
EXAMPLE 1 - PREPARATION
The electrode coatings were applied to gold or palladium electrodes by immersing the sheet of material from which the electrodes were made into a 1 mM aqueous solution of the coating compound adjusted to pH 12 by the addition of potassium hydroxide. The contact time between the electrode material and the coating bath was typically 30 seconds. After coating, the electrodes were washed by immersion in a bath of water. In some cases, the electrodes were immersed in a third bath containing 1,000 ppm of triton X-100 in water. Finally, the electrode material sheets were dried by blowing with air at room temperature. EXAMPLE 2 - STORAGE
The data in Tables 1 and 2 below show the effect on the electrode stability of coating the electrodes with sulphur-containing compounds. The stability was assessed using an accelerated test. The glucose sensors using coated or uncoated electrodes were stored either at 4°C in the refrigerator ("fridge") or at 56°C in an oven for two weeks. The sensors stored at 4°C do not change significantly from their performance when freshly prepared and tested. Those stored in the oven are subject to accelerated ageing, which simulates longer ageing times at room temperature. EXAMPLE 3 - TESTING
After two weeks the sensors were tested with whole blood samples with various glucose concentrations, from about 3 mM to 30 mM. The background ferrocyanide concentration was measured (the reading obtained when a sample contains no glucose) and the overall precision and fill speed of the sensors was assessed. The effect of the electrode coatings is shown in Table 1. The fill speeds in Table 1 were assessed qualitatively by eye. The fill speeds in Table 2 were assessed quantitatively by videoing the filling of the sensor with a blood sample using an on-screen timer and subsequently determining the number of seconds required for the blood to fill each sensor.
It can be seen from the first pair of results, for a non-coated electrode, that artificial ageing dramatically increased the %cv (corresponding to decreased precision).
In contrast, for the last two pairs of results, the %cv's for the treated electrodes after artificial ageing were comparable to the %cv's of untreated electrodes on fridge storage and significantly better than accelerated aged untreated electrodes.
A desirable side effect of the present invention also appears to be maintenance of good fill speed for sensors on ageing.
TABLE 1 TEST DATA
STORAGE COATING BACKGROUND MEAN %cv FILL SPEED
(mM ferrocyanide)
Fridge None 1.01 3.8 OK
Oven None 5.12 10.05 very slow
Fridge Cysteine 1.3 4.5 OK
Oven Cysteine 5.0 8.0 slow
Fridge Cysteine/trit 1.98 3.1 fast
Oven Cysteine/trit 2.17 5.4 OK
Fridge Homocysteine 1.02 4.6 OK /trit
Oven Homocysteine 2.34 4.2 faster than /trit Cysteine/trit
Fridge Cystine/trit 0.63* 4.1 fast
Oven Cystine/trit 1.24* 4.4 good
Figure imgf000007_0001
- 6 -
* saline rather than blood used to assess the background Trit denotes an overcoating of Triton X-100.
TABLE 2 PRECISE FILL TIMES
STORAGE COATING FILL TIME (sees)
Fridge none 1.0
Oven none 5.3
Fridge Cystine 0.4
Oven Cystine 4.0
Fridge Cystine/trit 0.3
Oven Cystine/trit 1.4
Figure imgf000008_0001
A person skilled in the art will appreciate that the application process is very simple and facile and could be accomplished from the teaching hereof in many ways.

Claims

-7- THE CLAIMS OF THE INVENTION ARE AS FOLLOWS
I . A metal electrode stabilised by a coating, the coating comprising a sulfur containing moiety in its molecular structure. 2. A metal electrode according to Claim 1 wherein the sulfur containing moiety is selected from the group consisting of thiol, disulfide and SOx.
3. A metal electrode according to Claim 2 wherein the sulfur containing moiety is a disulfide.
4. A method according to any one of the preceding claims wherein the sulfur containing moiety is further incorporated in a cyclic structure.
5. A metal electrode according to any one of claims 1 to 4 stabilised by a coating, said coating comprising a sulfur containing moiety and a hydrophilic group in its molecular structure.
6. A metal electrode according to Claim 5 wherein the hydrophilic group is selected from the group consisting of hydroxyl, amine, carboxyl, carbonyl, oligo (ethyleneoxide) chain, and zwitterionic species.
7. A metal electrode according to Claim 6 wherein the hydrophilic group is a zwitterionic species.
8. A metal electrode according to Claim 7 wherein the zwitterionic species includes an amine and a carboxyl group in proximity.
9. A metal electrode according to any one of the preceding claims stabilised by a coating, said coating comprising a sulfur containing moiety, a hydrophilic group, and a spacer between the sulfur containing moiety and the hydrophilic group in its molecular structure. 10. A metal electrode according to Claim 9 wherein the spacer is an alkyl group or an aromatic group.
I I. A metal electrode according to Claim 10 wherein the alkyl group includes methylene and/or ethylene groups as part of the spacer element.
12. A metal electrode according to any one of the preceding claims wherein the coating is selected from the group consisting of 2-mercaptoethanol, 2-mercaptoethylamine, 3 mercaptopropionic acid, thiophen, 4-carboxythiophen, cysteine, homocysteine, and cystine. - 8 -
13. A metal electrode according to any one of the preceding claims wherein the compound is the D or L isomer.
14. A metal electrode according to any one of claims 1 to 12 wherein the compound is a mixture of D and L isomers. 15. A metal electrode according to any one of the preceding claims further including an overcoating of surfactant.
16. A method of preparing a metal electrode stabilised by a coating, including the step of contacting a metal electrode with a substance, said substance including a sulfur containing moiety in its molecular structure. 17. A method according to claim 16 comprising the step of contacting a metal electrode with a substance including a sulfur containing moiety and a hydrophilic group in its molecular structure.
18. A method according to claim 16 or 17, comprising the step of contacting a metal electrode with a substance comprising a sulfur containing moiety, a hydrophilic group and a spacer between the sulfur containing moiety and the hydrophilic group in its molecular structure.
19. A method according to any one of claims 16 to 18 wherein the coating includes compounds selected from the group consisting of 2-mercaptoethanol, 2- mercaptoethylamine, 3-mercaptopropionic acid, thiophen, 4-carboxythiophen, cysteine, homocysteine, and cystine.
20. A method according to any one of claims 16 to 19 wherein the compound is the D or L isomer.
21. A method according to any one of claims 16 to 19 wherein the compound is a mixture of D and L isomers. 22. A method according to any one of claims 16 to 21 wherein the coating is applied as a monolayer or multilayer on the surface of an electrode.
23. A method according to any one of claims 16 to 22 wherein the coating material is applied by deposition from the vapour phase or from solution.
24. A method according to any one of claims 16 to 23 wherein the substance is applied by a method selected from the group consisting of dipping, spraying, painting, and printing. - 9 -
25. A method according to any one of claims 16 to 24 further including the step of overcoating the substance including a sulfur containing moiety in its molecular structure with a surfactant layer.
26. A method according to claim 25 wherein the surfactant layer and sulfur containing layer are applied simultaneously.
27. A method according to claim 25 wherein the surfactant layer is applied to the electrode subsequent to the application of the coating compound.
28. A method of sensing an analyte including the step of substituting the electrode in a known sensor device with a metal electrode stabilised by a coating according to any one of the preceding claims, and sensing an analyte.
PCT/AU1999/000166 1998-03-20 1999-03-16 Sensor with improved shelf life WO1999049307A1 (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
JP2000538226A JP2002507744A (en) 1998-03-20 1999-03-16 Sensor with improved shelf life
AU29136/99A AU745414B2 (en) 1998-03-20 1999-03-16 Sensor with improved shelf life
CA002322454A CA2322454C (en) 1998-03-20 1999-03-16 Sensor with improved shelf life
EP99910013A EP1084397A4 (en) 1998-03-20 1999-03-16 Sensor with improved shelf life
US09/664,688 US6652734B1 (en) 1999-03-16 2000-09-19 Sensor with improved shelf life
US10/630,441 US7335292B2 (en) 1998-03-20 2003-07-29 Sensor with improved shelf life
US11/926,369 US20080121533A1 (en) 1998-03-20 2007-10-29 Sensor with improved shelf life

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AUPP2503 1998-03-20
AUPP2503A AUPP250398A0 (en) 1998-03-20 1998-03-20 Sensor with improved shelf life

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US09/664,688 Continuation US6652734B1 (en) 1998-03-20 2000-09-19 Sensor with improved shelf life

Publications (1)

Publication Number Publication Date
WO1999049307A1 true WO1999049307A1 (en) 1999-09-30

Family

ID=3806765

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/AU1999/000166 WO1999049307A1 (en) 1998-03-20 1999-03-16 Sensor with improved shelf life

Country Status (6)

Country Link
EP (1) EP1084397A4 (en)
JP (1) JP2002507744A (en)
AU (1) AUPP250398A0 (en)
CA (1) CA2322454C (en)
TW (1) TW584724B (en)
WO (1) WO1999049307A1 (en)

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1329395A1 (en) 2002-01-16 2003-07-23 Lifescan, Inc. Test strip dispenser
EP1362801A2 (en) 2002-04-02 2003-11-19 Lifescan, Inc. Test strip containers and methods of using the same
US6676995B2 (en) 2001-11-28 2004-01-13 Lifescan, Inc. Solution striping system
EP1398386A1 (en) * 2002-09-12 2004-03-17 Lifescan, Inc. Mediator stabilized reagent compositions and methods for their use in electrochemical analyte detection assays
US6716577B1 (en) 2000-02-02 2004-04-06 Lifescan, Inc. Electrochemical test strip for use in analyte determination
EP1421899A1 (en) 2001-10-10 2004-05-26 Lifescan, Inc. Devices for physiological fluid sampling and methods of using the same
US6749887B1 (en) 2001-11-28 2004-06-15 Lifescan, Inc. Solution drying system
US6855243B2 (en) 2001-04-27 2005-02-15 Lifescan, Inc. Electrochemical test strip having a plurality of reaction chambers and methods for using the same
EP1611837A2 (en) 2004-06-30 2006-01-04 Lifescan Scotland Ltd Fluid handling devices
EP1612429A2 (en) 2004-06-30 2006-01-04 Lifescan Scotland Ltd Microfluidic flow modulation device
CN1315216C (en) * 2005-10-14 2007-05-09 北京工业大学 Platinum bimetal electrode catalyst using cysteine as coupling layer and its preparing method
EP2283770A1 (en) 2001-06-12 2011-02-16 LifeScan, Inc. Biological fluid constituent sampling and measurement devices and methods
US9863942B2 (en) 2002-03-21 2018-01-09 Universal Biosensors Pty Ltd Biosensor apparatus and methods of use

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1991009304A1 (en) * 1989-12-11 1991-06-27 United States Department Of Energy Enzyme electrical sensor electrode and method of making it
WO1997043274A1 (en) * 1996-05-13 1997-11-20 Australian Membrane And Biotechnology Research Institute Improved reservoir components

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
IL118432A (en) * 1996-05-27 1999-12-31 Yissum Res Dev Co Electrochemical and photochemical electrodes and their use

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1991009304A1 (en) * 1989-12-11 1991-06-27 United States Department Of Energy Enzyme electrical sensor electrode and method of making it
WO1997043274A1 (en) * 1996-05-13 1997-11-20 Australian Membrane And Biotechnology Research Institute Improved reservoir components

Non-Patent Citations (5)

* Cited by examiner, † Cited by third party
Title
DONG S, LI J: "SELF-ASSEMBLED MONOLAYERS OF THIOLS ON GOLD ELECTRODES FOR BIOELECTROCHEMISTRY AND BIOSENSORS", BIOELECTROCHEMISTRY AND BIOENERGETICS., XX, XX, vol. 42, no. 01, 1 January 1997 (1997-01-01), XX, pages 07 - 13, XP001062561, ISSN: 0302-4598, DOI: 10.1016/S0302-4598(96)05172-0 *
HE P, ET AL.: "SELF-ASSEMBLED BIOTINYLATED DISULFIDE DERIVATIVE MONOLAYER ON GOLD ELCTRODE FOR IMMOBILIZING ENZYMES", TALANTA, ELMSFORD,NY, US, vol. 44, no. 05, 1 January 1997 (1997-01-01), US, pages 885 - 890, XP001038392, DOI: 10.1016/S0039-9140(96)02133-9 *
KAJIYA Y, OKAMOTO T, YONEYAMA H: "GLUCOSE SENSITIVITY OF THIOL-MODIFIED GOLD ELECTRODES HAVING IMMOBILIZED GLUCOSE OXIDASE AND 2-AMINOCTHYLFERROCENE", CHEMISTRY LETTERS, CHEMICAL SOCIETY OF JAPAN, JAPAN, vol. 12, 1 January 1993 (1993-01-01), JAPAN, pages 2107 - 2110, XP001062321, ISSN: 0366-7022, DOI: 10.1246/cl.1993.2107 *
MIZUTANI F, ET AL.: "GLUCOSE OXIDASE/POLYION COMPLEX-BILAYER MEMBRANE FOR ELIMINATION OF ELECTROACTIVE INTERFERENTS IN AMPEROMETRIC GLUCOSE SENSOR", ANALYTICA CHIMICA ACTA, ELSEVIER, AMSTERDAM, NL, vol. 364, no. 01-03, 1 January 1998 (1998-01-01), NL, pages 173 - 179, XP001038387, ISSN: 0003-2670, DOI: 10.1016/S0003-2670(98)00003-8 *
See also references of EP1084397A4 *

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1254365B1 (en) * 2000-02-02 2009-11-25 Lifescan, Inc. Electrochemical test strip for use in analyte determination
US7498132B2 (en) 2000-02-02 2009-03-03 Lifescan, Inc. Electrochemical test strip kit for analyte determination
US6716577B1 (en) 2000-02-02 2004-04-06 Lifescan, Inc. Electrochemical test strip for use in analyte determination
US6855243B2 (en) 2001-04-27 2005-02-15 Lifescan, Inc. Electrochemical test strip having a plurality of reaction chambers and methods for using the same
EP2283770A1 (en) 2001-06-12 2011-02-16 LifeScan, Inc. Biological fluid constituent sampling and measurement devices and methods
EP2286720A1 (en) 2001-06-12 2011-02-23 LifeScan, Inc. Biological fluid constituent sampling and measurement devices and methods
EP1421899A1 (en) 2001-10-10 2004-05-26 Lifescan, Inc. Devices for physiological fluid sampling and methods of using the same
US6689411B2 (en) 2001-11-28 2004-02-10 Lifescan, Inc. Solution striping system
US6749887B1 (en) 2001-11-28 2004-06-15 Lifescan, Inc. Solution drying system
US6676995B2 (en) 2001-11-28 2004-01-13 Lifescan, Inc. Solution striping system
EP1329395A1 (en) 2002-01-16 2003-07-23 Lifescan, Inc. Test strip dispenser
US9863942B2 (en) 2002-03-21 2018-01-09 Universal Biosensors Pty Ltd Biosensor apparatus and methods of use
EP1362801A2 (en) 2002-04-02 2003-11-19 Lifescan, Inc. Test strip containers and methods of using the same
EP1398386A1 (en) * 2002-09-12 2004-03-17 Lifescan, Inc. Mediator stabilized reagent compositions and methods for their use in electrochemical analyte detection assays
US7291256B2 (en) 2002-09-12 2007-11-06 Lifescan, Inc. Mediator stabilized reagent compositions and methods for their use in electrochemical analyte detection assays
EP1612429A2 (en) 2004-06-30 2006-01-04 Lifescan Scotland Ltd Microfluidic flow modulation device
EP1611836A2 (en) 2004-06-30 2006-01-04 Lifescan Scotland Ltd Fluid handling methods
EP1611837A2 (en) 2004-06-30 2006-01-04 Lifescan Scotland Ltd Fluid handling devices
CN1315216C (en) * 2005-10-14 2007-05-09 北京工业大学 Platinum bimetal electrode catalyst using cysteine as coupling layer and its preparing method

Also Published As

Publication number Publication date
EP1084397A4 (en) 2003-06-25
EP1084397A1 (en) 2001-03-21
CA2322454C (en) 2008-01-08
TW584724B (en) 2004-04-21
CA2322454A1 (en) 1999-09-30
JP2002507744A (en) 2002-03-12
AUPP250398A0 (en) 1998-04-23

Similar Documents

Publication Publication Date Title
US6652734B1 (en) Sensor with improved shelf life
CA2322454C (en) Sensor with improved shelf life
Hagenström et al. Modification of a Au (111) electrode with ethanethiol. 1. Adlayer structure and electrochemistry
Lingler et al. Fusion of small unilamellar lipid vesicles to alkanethiol and thiolipid self-assembled monolayers on gold
Wirde et al. Self-assembled monolayers of cystamine and cysteamine on gold studied by XPS and voltammetry
Tan et al. Constructing thromboresistant surface on biomedical stainless steel via layer-by-layer deposition anticoagulant
Calvente et al. Desorption of spontaneously adsorbed and electrochemically readsorbed 2-mercaptoethanesulfonate on Au (111)
Bowden et al. Interfacial electrochemistry of cytochrome c at tin oxide, indium oxide, gold, and platinum electrodes
KR100568916B1 (en) Modification of surfaces in order to increase surface tension
Kudelski Chemisorption of 2-mercaptoethanol on silver, copper, and gold: direct Raman evidence of acid-induced changes in adsorption/desorption equilibria
Wang et al. Electrocatalytic response of dopamine at a thiolactic acid self-assembled gold electrode
Cheng et al. Comparative study of electrochemically directed assembly versus conventional self-assembly of thioacetyl-terminated oligo (phenylene ethynylene) s on gold and platinum surfaces
Rosink et al. Self-assembly of π-conjugated azomethine oligomers by sequential deposition of monomers from solution
WO2018079509A1 (en) Gas sensor device and method for removing gas components
Campiña et al. Selective permeation of a liquidlike self-assembled monolayer of 11-amino-1-undecanethiol on polycrystalline gold by highly charged electroactive probes
CA3142127A1 (en) Omniphobic surfaces with hierarchical structures, and methods of making and uses thereof
Zhang et al. Determination of ethamsylate in the presence of catecholamines using 4-amino-2-mercaptopyrimidine self-assembled monolayer gold electrode
Sun et al. Chitosan coated capillary with reversed electroosmotic flow in capillary electrophoresis for the separation of basic drugs and proteins
Kikuchi et al. Quartz crystal microbalance (QCM) sensor for CH3SH gas by using polyelectrolyte-coated sol–gel film
Khajavian et al. Tuning surface wettability of aluminum surface and its correlation with short and long term corrosion resistance in saline solutions
Bandyopadhyay et al. Selective K+ recognition at the interface during self-assembly of a bis-podand thiol on a gold surface
Wang et al. Electrocatalytic response of dopamine at a metallothioneins self-assembled gold electrode
AU745414B2 (en) Sensor with improved shelf life
JP2972858B2 (en) Method for measuring dynamic contact angle of sulfur-containing organic molecule self-assembled film
Wang et al. Poly (ester‐sulfonic acid)‐coated mercury film electrodes for anodic stripping voltammetry

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AL AM AT AU AZ BA BB BG BR BY CA CH CN CU CZ DE DK EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT UA UG US UZ VN YU ZA ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW SD SL SZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN GW ML MR NE SN TD TG

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
WWE Wipo information: entry into national phase

Ref document number: 29136/99

Country of ref document: AU

ENP Entry into the national phase

Ref document number: 2322454

Country of ref document: CA

Kind code of ref document: A

Ref document number: 2322454

WWE Wipo information: entry into national phase

Ref document number: 09664688

Country of ref document: US

NENP Non-entry into the national phase

Ref country code: KR

WWE Wipo information: entry into national phase

Ref document number: 1999910013

Country of ref document: EP

REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

WWP Wipo information: published in national office

Ref document number: 1999910013

Country of ref document: EP

NENP Non-entry into the national phase

Ref country code: CA

WWG Wipo information: grant in national office

Ref document number: 29136/99

Country of ref document: AU