Abstract: An electronic circuit for sensing an output of a sensor having at least one electrode pair and circuitry for obtaining and processing the sensor output. The electrode pair may be laid out such that one electrode is wrapped around the other electrode in a U-shaped fashion. The electronic circuitry may include, among other things, a line interface for interfacing with input/output lines, a rectifier in parallel with the line interface, a counter connected to the line interface and a data converter connected to the counter and the electrode pair. The data converter may be a current-to-frequency converter. In addition, the rectifier may derive power for the electronic circuit from communication pulses received on the input/output lines.

Abstract: A telemetered characteristic monitor system includes a remotely located data receiving device, a sensor for producing signal indicative of a characteristic of a user, and a transmitter device. The transmitter device includes a housing, a sensor connector, a processor, and a transmitter. The transmitter receives the signals from the sensor and wirelessly transmits the processed signals to the remotely located data receiving device. The processor coupled to the sensor processes the signals from the sensor for transmission to the remotely located data receiving device. The data receiving device may be a characteristic monitor, a data receiver that provides data to another device, an RF programmer for a medical device, a medication delivery device (such as an infusion pump), or the like.

Abstract: An implanted medical device (e.g. infusion pump) and external device communicate with one another via telemetry wherein messages are transmitted under a robust communication protocol. The communication protocol gives enhanced assurance concerning the integrity of messages that impact medical operations of the implantable device. Messages are transmitted using a multipart format that includes a preamble, a frame sync, a telemetry ID, data, and a validation code. The data portion of the message includes an op-code that dictates various other elements that form part of the message. The data portion may also include additional elements such as sequence numbers, bolus numbers, and duplicate data elements. A telemetry ID for the transmitting device may be implicitly embedded in the message as part of the validation code that is sent with the message and that must be pre-known by the receiver to confirm the integrity of the received message.

Abstract: A drive mechanism for delivery of infusion medium. A coil surrounds a piston channel. An armature is located adjacent the coil. The armature is moveable toward a forward position in response to the electromagnetic field produced by activation of the coil. A piston located within the piston channel is moveable within the channel to a forward position in response to movement of the armature. The armature and piston are moved toward a retracted position when the coil is not energized. In the retracted position, a piston chamber formed between the piston and a valve member is filled with infusion medium. As the piston is moved to its forward position, piston chamber volume is reduced and pressure within the piston chamber increases and moves the valve member into an open position. Medium from the piston chamber is then discharged into an outlet chamber.

Abstract: Methods are provided for the determination of the concentration of biological levels of polyhydroxylated compounds, particularly glucose. The methods utilize an amplification system that is an analyte transducer immobilized in a polymeric matrix, where the system is implantable and biocompatible. Upon interrogation by an optical system, the amplification system produces a signal capable of detection external to the skin of the patient. Quantitation of the analyte of interest is achieved by measurement of the emitted signal.

Abstract: A selectively protected electrical system includes or operates with a power source, a load, a power driver circuit for controllably transferring power from the power source to the load, the power driver circuit being encapsulated in a potting material, and a controller for enabling and disabling the power driver circuit, the controller being un-encapsulated by the potting material. If a contaminant induced electrical fault occurs in the selectively protected electrical system, the electrical fault is more likely to occur in the un-encapsulated controller, such that the selectively protected electrical system is disabled. The contaminant is inhibited from contacting and inducing an electrical fault in the power driver circuit, thus providing for a controlled failure of the selectively protected electrical system.

Abstract: An improved pump, reservoir and reservoir piston are provided for controlled delivery of fluids. A motor is operably coupled to a drive member, such as a drive screw, which is adapted to advance a plunger slide in response to operation of the motor. The plunger slide is removably coupled to the piston. The piston comprises a first member and a second member. The first member has an external proximate side and an external distal side. The external proximate side is adapted to contact the fluid and is made of a material having a first stiffness. The second member has a first side and a second side and is at least partially disposed within the first member. The first side of the second member is adjacent to the external proximate side of the first member and is made of a material having a stiffness which is greater than the first stiffness.

Abstract: A communication device (CD) exchanges messages with an implantable infusion pump via telemetry such that commands are supplied thereto and operational information is obtained therefrom. The CD is controlled, at least in part, by a processor IC according to a software program operating therein and provides feedback to a user via a visual display, an audio alarm, and a vibrational alarm, and allows input from the user via a touch sensitive keypad. Certain input functions are restricted by password. The visual display includes an icon and fixed element display region and a bitmap display region. The fixed element display region includes time and date displays, battery and drug level displays that decrement, and a moving delivery state display. Various screens allow operational or log information to be displayed and/or user entry of commands. Program features when disabled are removed from a series of screen options that can be scrolled through.

Abstract: A closed loop infusion system controls the rate that fluid is infused into the body of a user. The closed loop infusion system includes a sensor system, a controller, and a delivery system. The sensor system includes a sensor for monitoring a condition of the user. The sensor produces a sensor signal, which is representative of the condition of the user. The sensor signal is used to generate a controller input. The controller uses the controller input to generate commands to operate the delivery system. The delivery system infuses a liquid into the user at a rate dictated by the commands from the controller. Preferably, the sensor system monitors the glucose concentration in the body of the user, and the liquid infused by the delivery system into the body of the user includes insulin.

Abstract: An improved reservoir is provided for use in a medication infusion device for operating the reservoir to administer a fluid to a patient. The reservoir comprises a hollow barrel adapted to receive a supply of fluid for delivery through infusion tubing or the like to the patient, in combination with a reservoir plunger. The reservoir plunger is designed to engage a motor-driven lead screw of the medication infusion device.

Abstract: The present invention is directed to stabilized polypeptide compositions. Typical embodiments of the present invention provide improved methods and materials for maintaining the stability of insulin polypeptide formulations. In particular, the disclosure provided herein teaches that the aggregation of insulin polypeptides can be inhibited by combining them with a class of compounds having the general formula A1—L1—S—L2—A2, wherein S comprises from one to seven consecutive atoms selected from the group consisting of nitrogen, carbon, and oxygen, wherein at least one of the atoms is a carbon atom; L1 and L2 are linking groups having from two to twelve atoms selected from the group consisting of nitrogen, carbon, oxygen, sulfur, and phosphorus; and A1 and A2 are carboxylic acid groups.

Abstract: Methods for reducing the electrode impedance of implantable biosensors by coating the surface of the biosensor with a uniform hydrogel which allows unimpeded water movement around the sensor are provided. The surface coatings are compositions which are biocompatible and are capable of water uptake of at least 120% of their weight, more preferably at least 200% of their weight. Upon the uptake of water, the hydrogels used in the present invention will also swell and provide a layer of water around the electrodes to which the hydrogels are attached. The hydrogels can be prepared from (a) a diisocyanate, (b) a hydrophilic polymer which is a hydrophilic diol, a hydrophilic diamine, or a combination thereof, and optionally, (c) a chain extender.

Abstract: Methods and apparatuses for calculating and transmitting medication dosage or bolus information are provided. A blood glucose meter receives a test strip with a sample of the user's blood and measures the user's blood glucose level with a sensor. The meter then calculates a bolus amount that is transmitted to a medication infusion pump using a radio frequency transmitter or transceiver. The infusion pump receives the bolus amount data and then delivers a bolus of medication to the user based on the calculated bolus estimate. The meter may also transmit commands to, and be used to remotely control, the infusion pump.

Abstract: A holster is provided with a clip portion for clipping to a user's belt or other suitable location and a harness portion for holding an electronic device, such as, but not limited to, a medical infusion pump. The holster may include a rotation mechanism that allows the holster to be rotated in a manner, to position and maintain the electronic device in any one of a plurality of selectable rotational orientations, while the holster is clipped to the user's belt. Alternatively or in addition, the clip portion is pivotally connected by a hinge to the harness portion, to allow the harness portion to pivot upward relative to the clip portion. The pivotal connection of the clip portion to the harness portion allows the user pivot the harness portion (and, thus, a medical device received in the harness portion) upward, for example, to better accommodate the user's view or access to displays, indicators, compartments, buttons or other manual operators on the medical device.

Abstract: Embodiments of the invention provide polymer coated implantable medical devices having a bioactive material posited in or on at least a portion of the coating layer, wherein the coating layer provides for the controlled release of the bioactive material from the coating layer. Preferably, the medical device is an intravascular stent.

Abstract: A drive mechanism for delivery of infusion medium. A coil surrounds a piston channel. An armature is located adjacent the coil. The armature is moveable toward a forward position in response to the electromagnetic field produced by activation of the coil. A piston located within the piston channel is moveable within the channel to a forward position in response to movement of the armature. The armature and piston are moved toward a retracted position when the coil is not energized. In the retracted position, a piston chamber formed between the piston and a valve member filled with infusion medium. As the piston is moved to its forward position, piston chamber volume is reduced and pressure within the piston chamber increases and moves the valve member into an open position. Medium from the piston chamber is then discharged into an outlet chamber.

Abstract: A reusable analyte sensor site for use with a replaceable analyte sensor for determining a level of an analyte includes a site housing and a resealable insertion site coupled to one end of the site housing. Preferably, the site housing is formed to have an interior cavity, and includes an outer membrane made of a material selected to promote vascularization and having a first pore size, and an inner membrane made of a material selected to be free of tissue ingress. Also, the site housing permits the analyte to pass through the site housing to the interior cavity to permit measurement by the replaceable analyte sensor. The resealable insertion site is provided for inserting the replaceable analyte sensor into the interior cavity of the site housing.

Abstract: Fluorescent biosensor molecules, fluorescent biosensors and systems, as well as methods of making and using these biosensor molecules and systems are described. Embodiments of these biosensor molecules exhibit fluorescence emission at wavelengths greater than about 650 nm. Typical biosensor molecules include a fluorophore that includes an iminium ion, a linker moiety that includes a group that is an anilinic type of relationship to the fluorophore and a boronate substrate recognition/binding moiety, which binds glucose. The fluorescence molecules modulated by the presence or absence of polyhydroxylated analytes such as glucose. This property of these molecules of the invention, as well as their ability to emit fluorescent light at greater than about 650 nm, renders these biosensor molecules particularly well-suited for detecting and measuring in-vivo glucose concentrations.

Abstract: A method for formulating a glucose oxidase enzyme with peroxide resistant properties and a glucose oxidase enzyme formulated by the method. The enzyme formulation method results in a glucose oxidase enzyme with improve resistance to peroxide, and therefore, with improved resistance to oxidative inactivation. The method employs directed evolution techniques to evolve glucose oxidase to achieve the desirable properties. A peroxide resistant glucose oxidase may improve the longevity of, for example, glucose biosensors in which a peroxide resistant glucose oxidase may be placed.

Abstract: An occlusion detection system detects an occlusion in a fluid path of an infusion pump. The infusion pump is for delivering fluid to a user. The infusion pump includes a housing, a motor, a reservoir, one or more drive train components, a sensor, and an electronics system. The motor is contained within the housing. The reservoir contains the fluid to be delivered. The one or more drive train components react to stimulus from the motor to force the fluid from the reservoir into the user. The sensor is positioned to measure a parameter associated with the motor or a drive train component, and the sensor produces three or more output levels across a range of measurements. The electronics system processes the sensor output levels to declare when an occlusion exists.