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 body fluid sampling system is provided for use on a tissue site. In one embodiment, the system comprises a cartridge; a penetrating member driver; a plurality of penetrating members arranged in a radial configuration on the cartridge wherein sharpened distal tips of the penetrating members point radially outward; wherein an active one of the penetrating members may be operatively coupled to the penetrating member driver, the penetrating member driver moving the active one along a path out of a housing having a penetrating member exit, into the tissue site, stopping in the tissue site, and withdrawing out of the tissue site; and a plurality of analyte detecting members, wherein at least one of the analyte detecting members is positioned to receive fluid from a wound created by the active one of the penetrating members, wherein the detecting members are not pierced by the active one of the penetrating members.

Method and apparatus for body fluid sampling and analyte sensing

A tissue penetration device and method of using same that may include a lancet module or sampling module. The sampling module may optionally be in a cartridge configuration and include sampling and analyzing functions, which may be integrated.

Sampling module device and method

A reagent test strip for measuring an analyte concentration in a biological fluid has a spreading mesh sandwiched between a support and a reagent matrix. The support has a through hole that is covered by the mesh. In use, a sample of the fluid is applied through the hole in the support to the spreading mesh. The sample then passes through the mesh to the matrix, which contains a reagent that indicates the analyte concentration by causing a corresponding change in reflectance at its free surface. Optionally, an adhesive layer attaches the mesh, and optionally the matrix as well, to the support.

Koon-Wah Leong

Papers

Multi-layer reagent test strip