An analyte monitor includes a sensor, a sensor control unit, and a display unit. The sensor has, for example, a substrate, a recessed channel formed in the substrate, and conductive material disposed in the recessed channel to form a working electrode. The sensor control unit typically has a housing adapted for placement on skin and is adapted to receive a portion of an electrochemical sensor. The sensor control unit also includes two or more conductive contacts disposed on the housing and configured for coupling to two or more contact pads on the sensor. A transmitter is disposed in the housing and coupled to the plurality of conductive contacts for transmitting data obtained using the sensor. The display unit has a receiver for receiving data transmitted by the transmitter of the sensor control unit and a display coupled to the receiver for displaying an indication of a level of an analyte. The analyte monitor may also be part of a drug delivery system to alter the level of the analyte based on the data obtained using the sensor.

Analyte Monitoring Device And Methods Of Use

A sensor designed to determine the amount and concentration of analyte in a sample having a volume of less than about 1 μL. The sensor has a working electrode coated with a non-leachable redox mediator. The redox mediator acts as an electron transfer agent between the analyte and the electrode. In addition, a second electron transfer agent, such as an enzyme, can be added to facilitate the electrooxidation or electroreduction of the analyte. The redox mediator is typically a redox compound bound to a polymer. The preferred redox mediators are air-oxidizable. The amount of analyte can be determined by coulometry. One particular coulometric technique includes the measurement of the current between the working electrode and a counter or reference electrode at two or more times. The charge passed by this current to or from the analyte is correlated with the amount of analyte in the sample. Other electrochemical detection methods, such as amperometric, voltammetric, and potentiometric techniques, can also be used. The invention can be used to determine the concentration of a biomolecule, such as glucose or lactate, in a biological fluid, such as blood or serum. An enzyme capable of catalyzing the electrooxidation or electroreduction of the biomolecule is provided as a second electron transfer agent.

Small volume in vitro analyte sensor

A body fluid sampling system for use on a tissue site includes a single drive force generator. A plurality of penetrating members are operatively coupled to the force generator. The force generator moves each of the members along a path out of a housing with a penetrating member exit, into the tissue site, stops in the tissue site, and withdraws out of the tissue site. A flexible support member couples the penetrating members to define a linear array. The support member is movable and configured to move each of the penetrating members to a launch position associated with the force generator.

Method and Apparatus for Penetrating tissue

A tissue penetration device and method of using same. The tissue penetration device may optionally include sampling and analyzing functions, which may be integrated. An embodiment provides control of a lancet used for sampling blood. Electric field coils or solenoids may drive the lancet using electromagnetic force. Advancement and retraction of a lancet may be controlled by a feedback loop monitoring the position and velocity of the lancet embodiments of the lancet driver can be configured to follow a predetermined tissue lancing profile. Embodiments of the invention include a lancet and method for using a lancet to maintain the patency of the wound tract once the lancet has cut into the skin.

Tissue penetration device

A measurement module for glucose testing includes a glucose testing measurement module housing, a test strip receptacle formed in the housing, and a connector portion formed in the housing and shaped to permit mechanical removable attachment of the housing to a hand-held computer. Electronics determine the amount of glucose present in a sample of body fluid, when the test strip is positioned in the receptacle and the body fluid is placed on a test strip, and communicate the glucose amount to the hand-held computer via the connector portion.

Blood glucose tracking apparatus and methods

An immobilized enzyme electrode effective in measurement of the substrate concentration of the enzyme and in conversion from enzyme reaction energies into electric energies. The immobilized enzyme, of an oxidase system, such as glucose oxidase, amino acid oxidase, xanthine oxidase or the like and a metal oxide capable of constituting a redox system which is reduced through coupling with these enzyme reactions and is electrochemically oxidized (anodic oxidation) are combined with each other. The use of the enzyme electrode allows the determination quantity of the enzyme substrate as extremely low as approximately 10 -5 to 10 -6 mole/l in concentration.

Electrochemical measuring apparatus comprising enzyme electrode

Improvements in a coenzyme electrode used to electrochemically measure the activity of enzyme or substrate concentration of the enzyme easily. The coenzyme is immobilized, without using a semipermeable membrane, on the electron collector directly with the chemical bond, particularly the covalent bond, whereby the activity of the oxido-reductase requiring the coenzyme can be measured. In addition, the oxido-reductase requiring the coenzyme is also immobilized together with such immobilized coenzyme to improve the characteristics of the conventional enzyme-coenzyme immobilized electrode.

Coenzyme immobilized electrode

PURPOSE: To secure a quick and simple measurement of the substrate density as well as to realize the continuous and repetitive use of the enzyme electrode by securing the specific 3-lamination structure and thus giving the electrochemical activity to the substrate which suffers the peculiar catalyst function of the enzyme. CONSTITUTION: The electron conducting material such as the graphite powder is mixed well with the insoluble redox compound such as bromanil. Then a small amount of such mixture is unified with the electron conducting material through, for example, the press formation. In the moldings thus composed of 1st layer 1 made of the electron conducting material and 2nd layer 2 made of the electron conducting material and the insoluble redox compound, the oxidoreductase like glucose oxidase is fixed on layer 2 via glutaric aldehyde, and then 3rd layer 3 containing enzyme is formed. In such way, the enzyme electrode can be made with the minimum necessary amount of enzyme and the insoluble redox compound. COPYRIGHT: (C)1980,JPO&Japio

Enzyme electrode and its manufacture

PURPOSE:Electrochromic image display elements increased in response speed and improved in low-temperature performance characteristics, obtained by using as an electrolyte for electrochromic image display elements a liquid electrolyte obtd. by dissolving heteropolyacid in a nonaqueous solvent.

Image display elements

PURPOSE:To make the control of the procedure degree of the immobilization reaction of enzyme easy, by covering previously the surface of a carrier for immobilization of enzyme with an enzyme solution wherein a resin as well as the enzyme are dissolved in an organic solvent, drying the surface, followed by feeding an immobilizing reagent from a gas phase to it. CONSTITUTION:100mg/ml urease aqueous solution as an enzyme solution and 10g/ dl solution of polymethyl methacryrate in acetone as a resin solution are prepared. 1pts.wt. enzyme solution is blended with 9pts.wt. resin solution to give a mixed solution, which is applied to the sensitive part of the glass electrode 3 by dipping, etc. to cover the part with it. The covered part is dried to remove the solvent, and the immobilization reaction of the enzyme is carried out in the vapor of glutaraldehyde at 25 deg.C for 60-90min, to give the enzyme immobilization film 4 having sufficient adhesiveness and mechanical strength. After the reaction, the film is washed in a buffer solution of phosphoric acid. 2-Oxyadipaldehyde, acrolein, etc. besides, glutaraldehyde is used as the immobilizing reagent.

Nakamura Kenichi

Papers

Electrochemical measuring apparatus comprising enzyme electrode

Coenzyme immobilized electrode

Enzyme electrode and its manufacture

Image display elements

Immobilization of enzyme