WO2004060297A2 - Agents de reticulation hydrophiles s'utilisant dans des capteurs enzymatiques - Google Patents

Agents de reticulation hydrophiles s'utilisant dans des capteurs enzymatiques Download PDF

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Publication number
WO2004060297A2
WO2004060297A2 PCT/US2003/041060 US0341060W WO2004060297A2 WO 2004060297 A2 WO2004060297 A2 WO 2004060297A2 US 0341060 W US0341060 W US 0341060W WO 2004060297 A2 WO2004060297 A2 WO 2004060297A2
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WO
WIPO (PCT)
Prior art keywords
membrane
enzyme
oxidase
cross
glucose
Prior art date
Application number
PCT/US2003/041060
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English (en)
Other versions
WO2004060297A3 (fr
Inventor
William P. Van Antwerp
Original Assignee
Medtronic Minimed, 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 Medtronic Minimed, Inc. filed Critical Medtronic Minimed, Inc.
Priority to AU2003297503A priority Critical patent/AU2003297503A1/en
Priority to CA002511549A priority patent/CA2511549A1/fr
Priority to EP03814924A priority patent/EP1587546A4/fr
Publication of WO2004060297A2 publication Critical patent/WO2004060297A2/fr
Publication of WO2004060297A3 publication Critical patent/WO2004060297A3/fr

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    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12QMEASURING OR TESTING PROCESSES INVOLVING ENZYMES, NUCLEIC ACIDS OR MICROORGANISMS; COMPOSITIONS OR TEST PAPERS THEREFOR; PROCESSES OF PREPARING SUCH COMPOSITIONS; CONDITION-RESPONSIVE CONTROL IN MICROBIOLOGICAL OR ENZYMOLOGICAL PROCESSES
    • C12Q1/00Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions
    • C12Q1/001Enzyme electrodes
    • C12Q1/005Enzyme electrodes involving specific analytes or enzymes
    • C12Q1/006Enzyme electrodes involving specific analytes or enzymes for glucose
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12NMICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N11/00Carrier-bound or immobilised enzymes; Carrier-bound or immobilised microbial cells; Preparation thereof
    • C12N11/02Enzymes or microbial cells immobilised on or in an organic carrier
    • C12N11/06Enzymes or microbial cells immobilised on or in an organic carrier attached to the carrier via a bridging agent

Definitions

  • This invention relates generally to cross-linking agents for use with enzymatic sensors and to methods of making and using such materials.
  • the cross-linking agents are hydrophilic and suitable for use with enzymatic sensors for detecting analytes, such as glucose.
  • Biosensors are small devices that use biological recognition properties for selective detection of various analytes or biomolecules. Typically, the sensor will produce a signal that is quantitatively related to the concentration of the analyte. To achieve a quantitative signal, a recognition molecule or combination of molecules is often -mrnobiltzed at a suitable transducer, which converts the biological recognition event into a quantitative response.
  • the enzyme is immobilized onto the sensor via use of a cross-linking agent, such as glutaraldehyde.
  • a cross-linking agent such as glutaraldehyde.
  • a typical glucose sensor works by a reaction in which glucose reacts with oxygen in the presence of glucose oxidase (GOd) to form gluconolactone and hydrogen peroxide.
  • the gluconolactone further reacts with water to hydrolyze the lactone ring and produce gluconic acid.
  • the H 2 O 2 formed is electrochemically oxidized at an electrode as shown below (Equation 1):
  • the current measured by the sensor/potentiostat (+0.5 to +0.7 v oxidation at Pt black electrode) is the result of the two electrons generated by the oxidation of the H 2 O 2 .
  • the stoichiometry of the GOd reaction points to a challenge of developing a reliable glucose sensor. If oxygen and glucose are present in equi olar concentrations, then the H 2 O 2 is stoichiometricaUy related to the amount of glucose that reacts at the enzyme. In this case, the ultimate current is also proportional to the amount of glucose that reacts with the enzyme. If there is insufficient oxygen for all of the glucose to react with the enzyme, then the current will be proportional to the oxygen concentration, not the glucose concentration. For the sensor to be a true glucose sensor, glucose must be the limiting reagent, i.e. the 0 2 concentration must be in excess for all potential glucose concentrations.
  • the glucose concentration in the body of a diabetic patient can vary from 2 to 30 mM (rrii.limoles per liter or 36 to 540 mg/dl), whereas the typical oxygen concentration in the tissue is 0.02 to 0.2 mM (see, Fisher, et al., Biomed. Biochem. Acta. 48:965-971 (1989).
  • This ratio in the body means that the sensor would be running in the Michaelis Menten limited regime and would be very insensitive to small changes in the glucose concentration. This problem has been called the "oxygen deficit problem". Accordingly, a method or system must be devised to either increase the 0 2 in the GOd enzyme layer, decrease the glucose concentration, or devise a sensor that does not use 0 2 .
  • the invention provides a biocompatible membrane comprising an enzyme and a hyc-Jrophilic cross-linking agent, which membrane can be applied to a sensor.
  • an enzymatic sensor comprising an enzyme that generates a signal upon contact with an analyte; a substrate; and a cross-linking agent that comprises one or more hy ⁇ -kopkilic moieties.
  • the enzyme is immobilized onto the substrate via the hydrophilic cross-linking agent.
  • the enzymatic sensor provides enhanced sensing capabilities by improving the diffusion of reactive species and thereby increasing the overall sensitivity and lifetime of the sensor.
  • the incorporation of hydropliilic moieties into the cross-liriking agent optimizes hydration of the sensor and creates hydrophilic channels or pathways for reactive species, such as H 2 0 2 and the analyte of interest.
  • the one or more hydrophilic moieties comprise a polyol selected from the group consisting of polyethylene glycol, polypropylene glycol and a copolymer of polypropylene glycol and polyethylene glycol
  • the cross-linking agent comprises an aldehyde, diimrnide, cyanate, isocyanate, or diisocyanate.
  • a typical cross-linking agent of the invention comprises: PEG
  • R is an aldehyde, diimmide, cyanate, isocyanate, or diisocyanate
  • N is an integer from 1 to about 10. In some embodiments, N is 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10.
  • the invention additionally provides a method of measuring an analyte in a tissue of a subject.
  • the method comprises introducing an enzymatic sensor of the invention into the tissue of the subject, and detecting the signal generated by die enzyme.
  • the amount of signal corresponds to the amount of analyte.
  • the analyte is glucose and the enzyme is glucose oxidase.
  • adherered to or “adhered thereto” means stuck to or fused with such that a substance adhered to a surface remains substantially attached to or closely associated with the surface.
  • the invention is based on the discovery that hy ⁇ -bophi-ic cross-linking agents can be used in enzymatic sensors, resulting in sensors with improved hydration and enhanced sensitivity.
  • the invention provides a biocompatible membrane comprising an enzyme that generates a signal upon contact with an analyte, a substrate, and a hydrophilic cross-linking agent.
  • the enzyme is immobilized in the substrate via the hyt-kophilic cross-linking agent.
  • the cross-linking agent comprises one or more hy ⁇ -hOphilic moieties.
  • the membrane can be applied to a sensor to produce an enzymatic sensor.
  • the enzymatic sensors of the invention provide enhanced sensing capabilities by improving the diffusion of reactive species and thereby increasing the overall sensitivity and lifetime of the sensors.
  • the incorporation of hy ⁇ -bophilic moieties into the cross-linking agent optimizes hydration of the sensor and creates hy ⁇ - Opbilic channels or pathways for reactive species, such as H 2 O and the analyte of interest.
  • the increased hydration of the sensor environment may also reduce the formation of a skin over the sensor membrane, as occurs with use of the conventional cross-linking agent, glutar aldehyde.
  • the cross-linking agents of the invention avoid or diminish negative consequences of e-beam sterilization of sensors that occurs with conventional cross-linking agents. For example, glutaraldehyde and other conventional cross-linking agents can leave by-products that damage the sensor during e-beam sterilization.
  • a glucose sensor intended for in vivo use requires that the supply of oxygen in the vicinity of the sensing element not be depleted. Additionally, the glucose should diffuse to the sensor at a controlled rate. This diffusion of the analyte to the sensor occurs through a membrane adhered to the surface of the sensor. Overall, the membrane should control the relative rates of diffusion of oxygen and glucose to the sensor so that the local concentration of oxygen is not depleted. Additionally, glucose sensors intended for in vivo use must also be biocompatible with the body. Thus, the enzyme(s) used in such sensors must be protected from degradation or denaturation, while the elements of such sensors must be protected from molecules that would foul the sensors or their accuracy will decrease over time.
  • the present invention provides a biocompatible membrane comprising an enzyme immobilized in a substrate by a hydrophilic cross- linking agent.
  • the substrate is typically a polymer matrix. Suitable polymeric compositions are known in the art (see, e.g., U.S. Patent Nos. 5,777,060 and 5,786,439, both of which are incorporated herein by reference).
  • the hydrophilic cross-linking agent comprises a cross-linking agent that includes one or more hydi-ophilic moieties. Examples of cross-linldng agents having hydrophilic moieties are described below.
  • the homogeneity of the membrane can be further enhanced by introducing hydrophilic moieties into other proteins present in the membrane.
  • hydrophilic moieties For example, pegylation of albumin, glucose oxidase, or other enzyme present in the membrane would create an even more homogeneous structure.
  • the biocompatible membrane of the invention comprises a polymeric composition that contains an enzyme that generates a signal upon contact with an analyte of interest.
  • the enzyme is immobilized in the composition or membrane that covers the sensor via a cross-linldng agent.
  • cross-linking agents suitable for use with the invention include, but are not limited to, molecules that comprise aldehydes, diimmides, cyanates, isocyanates, and diisocyanates, into which hydrophilic moieties are incorporated.
  • hydrophilic moieties include, but are not limited to: polyols, such as polyethylene glycol, polypropylene glycol and copolymers of polypropylene glycol and polyethylene glycol; and other non-ionic surfactants, including Tweens 20-80.
  • hydrophilic cross-linldng agents include:
  • R is an aldehyde, diimmide, cyanate, isocyanate, or diisocyanate
  • N is an integer from 1 to about 10. In some embodiments, N is 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10.
  • Biosensors typically include a transducer, or enzyme, that generates a signal upon contact with an analyte of interest, and is adhered to a detector, such as an electrode.
  • a transducer or enzyme
  • glucose sensors suitable for in vivo use can be prepared by depositing a membrane comprising a glucose sensitive enzyme, such as glucose oxidase, onto an electrode via an electromotive plating process.
  • the membrane can be applied by immersion of the sensor in a bath comprising glucose oxidase, a stabilizing protein, a surfactant and a buffer for conductivity and stability of the protein solution, and the enzyme is then deposited onto the electrode potentiometrically.
  • the membrane can be applied using a microelectrogravimetric plating method, such as is described in U.S. Patent No. 6,340,021, issued January 22, 2002.
  • the invention provides a sensor for measuring an analyte of interest in biological tissue, the sensor having a coating comprising a biocompatible membrane of the invention that includes an enzyme serving as a transducer that generates a signal upon contact with the analyte.
  • the sensor can be used in vitro, or is suitable for use as an implantable biosensor or other in vivo applications.
  • the analyte is glucose and the transducer is glucose oxidase.
  • enzymes can serve as transducers as appropriate for the analyte of interest and examples of such enzymes include, but are not limited to, ⁇ -hydroxy oxidase, lactate oxidase, urease, creatine amidohydrolase, creatine amidinohydrolase, sarcosine oxidase, glutamate dehydrogenase, pyruvate kinase, long chain alcohol oxidase, lactate dehydrogenase, and fructose dehydrogenase.
  • the invention additionally provides a method of measuring an analyte in a tissue of a subject.
  • the method comprises introducing an enzymatic sensor of the invention into the tissue of the subject, and detecting the signal generated by the enzyme.
  • the amount of signal generated corresponds to the amount of analyte.
  • the analyte is glucose and the enzyme is glucose oxidase.
  • the sensor is typically introduced into the tissue in vivo, via subcutaneous implantation, although those skilled in the art will appreciate other means for introducing the sensor into the tissue.

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  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Organic Chemistry (AREA)
  • Wood Science & Technology (AREA)
  • Zoology (AREA)
  • Engineering & Computer Science (AREA)
  • Bioinformatics & Cheminformatics (AREA)
  • Genetics & Genomics (AREA)
  • General Engineering & Computer Science (AREA)
  • Biotechnology (AREA)
  • Microbiology (AREA)
  • Biochemistry (AREA)
  • Proteomics, Peptides & Aminoacids (AREA)
  • General Health & Medical Sciences (AREA)
  • Biophysics (AREA)
  • Molecular Biology (AREA)
  • Immunology (AREA)
  • Analytical Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Emergency Medicine (AREA)
  • Biomedical Technology (AREA)
  • Measuring Or Testing Involving Enzymes Or Micro-Organisms (AREA)
  • Apparatus Associated With Microorganisms And Enzymes (AREA)
  • Immobilizing And Processing Of Enzymes And Microorganisms (AREA)

Abstract

L'invention concerne un capteur enzymatique qui comprend une enzyme produisant un signal lorsqu'elle entre en contact avec un analyte ; un substrat ; et un agent de réticulation qui comprend une ou plusieurs fractions hydrophiles. L'enzyme est immobilisée dans le substrat au moyen de l'agent de réticulation hydrophile. On applique une membrane biocompatible qui comprend l'enzyme, le substrat et l'agent de réticulation hydrophile sur un capteur afin de former un capteur enzymatique. Le capteur enzymatique présente des fonctions de détection renforcées en ce qu'il améliore la diffusion des espèces réactives, ce qui accroît la sensibilité générale et la durée de vie du capteur. L'incorporation de fractions hydrophiles dans l'agent de réticulation permet d'optimiser l'hydratation du capteur et de former des canaux ou voies hydrophiles pour les espèces réactives, telles que H202 et l'analyte étudié. La membrane et le capteur enzymatique peuvent être utilisés dans un procédé de détection d'un analyte tel que le glucose.
PCT/US2003/041060 2002-12-31 2003-12-19 Agents de reticulation hydrophiles s'utilisant dans des capteurs enzymatiques WO2004060297A2 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
AU2003297503A AU2003297503A1 (en) 2002-12-31 2003-12-19 Hydrophilic cross-linking agents for use in enzymatic sensors
CA002511549A CA2511549A1 (fr) 2002-12-31 2003-12-19 Agents de reticulation hydrophiles s'utilisant dans des capteurs enzymatiques
EP03814924A EP1587546A4 (fr) 2002-12-31 2003-12-19 Agents de reticulation hydrophiles s'utilisant dans des capteurs enzymatiques

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US33550602A 2002-12-31 2002-12-31
US10/335,506 2002-12-31

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WO2004060297A2 true WO2004060297A2 (fr) 2004-07-22
WO2004060297A3 WO2004060297A3 (fr) 2005-05-06

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EP (1) EP1587546A4 (fr)
AU (1) AU2003297503A1 (fr)
CA (1) CA2511549A1 (fr)
WO (1) WO2004060297A2 (fr)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2011041715A3 (fr) * 2009-10-01 2011-05-26 Medtronic Minimed, Inc. Appareils de détection d'analytes comportant des membranes de rejet d'interférences, et procédés de fabrication et d'utilisation de ceux-ci
US9493805B2 (en) 2001-06-01 2016-11-15 Colorado State University Research Foundation Enzymatic biosensors with enhanced activity retention for detection of organic compounds
US9493806B2 (en) 2001-06-01 2016-11-15 Colorado State University Research Foundation Enzymatic biosensing systems
US9796998B2 (en) 2007-04-09 2017-10-24 Colorado State University Research Foundation Oxygenase-based biosensing systems for measurement of halogenated alkene concentrations
US9896712B2 (en) 2011-08-02 2018-02-20 Colorado State University Research Foundation Biosensing system with extended lifetime via cofactor recycling
US10024797B2 (en) 2010-11-22 2018-07-17 Colorado State University Research Foundation Biosensing systems for measurement of lactose
US10618806B2 (en) 2017-05-23 2020-04-14 International Business Machines Corporation Neuro-chemical sensor with selectively permeable membrane on nano-electrode

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US6485703B1 (en) * 1998-07-31 2002-11-26 The Texas A&M University System Compositions and methods for analyte detection
US20030219404A1 (en) * 1999-12-24 2003-11-27 Motoo Yamasaki Branched polyalkylene glycols

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US5786439A (en) * 1996-10-24 1998-07-28 Minimed Inc. Hydrophilic, swellable coatings for biosensors
US5874165A (en) * 1996-06-03 1999-02-23 Gore Enterprise Holdings, Inc. Materials and method for the immobilization of bioactive species onto polymeric subtrates

Patent Citations (3)

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US6485703B1 (en) * 1998-07-31 2002-11-26 The Texas A&M University System Compositions and methods for analyte detection
WO2001022820A1 (fr) * 1999-09-30 2001-04-05 The General Hospital Corporation Utilisation de pramipexole pour traiter l'etat de besoin de cocaine
US20030219404A1 (en) * 1999-12-24 2003-11-27 Motoo Yamasaki Branched polyalkylene glycols

Non-Patent Citations (3)

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Title
KAKU T. ET AL: 'AMPERIMETRIC GLUCOSE SENSORS BASED ON IMMOBILIZED GLUCOSE OXIDASE-POLYQUINONE SYSTEM' ANAL. CHEM. vol. 66, 1994, pages 1231 - 1235, XP000446067 *
See also references of EP1587546A2 *
YANG Y-Y. ET AL: 'POE-PEG-POE triblock copolymeric microspheres containing protein I. Preparation and characterization' JOURNAL OF CONTROLLED RELEASE vol. 75, 2001, pages 115 - 128, XP004254408 *

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9493805B2 (en) 2001-06-01 2016-11-15 Colorado State University Research Foundation Enzymatic biosensors with enhanced activity retention for detection of organic compounds
US9493806B2 (en) 2001-06-01 2016-11-15 Colorado State University Research Foundation Enzymatic biosensing systems
US9796998B2 (en) 2007-04-09 2017-10-24 Colorado State University Research Foundation Oxygenase-based biosensing systems for measurement of halogenated alkene concentrations
WO2011041715A3 (fr) * 2009-10-01 2011-05-26 Medtronic Minimed, Inc. Appareils de détection d'analytes comportant des membranes de rejet d'interférences, et procédés de fabrication et d'utilisation de ceux-ci
US10024797B2 (en) 2010-11-22 2018-07-17 Colorado State University Research Foundation Biosensing systems for measurement of lactose
US9896712B2 (en) 2011-08-02 2018-02-20 Colorado State University Research Foundation Biosensing system with extended lifetime via cofactor recycling
US10618806B2 (en) 2017-05-23 2020-04-14 International Business Machines Corporation Neuro-chemical sensor with selectively permeable membrane on nano-electrode
US10669153B2 (en) 2017-05-23 2020-06-02 International Business Machines Corporation Neuro-chemical sensor with selectively permeable membrane on nano-electrode

Also Published As

Publication number Publication date
WO2004060297A3 (fr) 2005-05-06
AU2003297503A1 (en) 2004-07-29
EP1587546A4 (fr) 2007-02-14
EP1587546A2 (fr) 2005-10-26
CA2511549A1 (fr) 2004-07-22
AU2003297503A8 (en) 2004-07-29

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