摘要:
An implantable coaxial lead includes a cable with male and female connectors. The cable includes inner and outer helical coils separated by an inner insulator tube, with an outer insulator tube surrounding the outer helical coil. The male connector includes an outer conductive cylinder, a conductive pin and an insulator molded in between. For increased strength, a braided cylinder, infused with rubber, is included at the juncture of the male connector and the cable. The female connector includes a cylinder formed by two conducting body elements and an intervening insulating body element. The female connector includes respective conductive tension elements configured to engage the male connector. A first seal is provided between the conductive tension members for electrical isolation and tactile feedback. An insertion tool includes a cylinder with a hollow bore and detachable head, and a rod for pulling the lead through the cylinder.
摘要:
An electrochemical sensor includes electronic circuitry for automatically performing on a periodic basis, e.g., every 1 to 24 hours, specified integrity tests which verify proper operation of the sensor.
摘要:
A protective, biocompatible coating or encapsulation material protects and insulates a component or device intended to be implanted in living tissue. The coating or encapsulation material includes a thin layer or layers of alumina, zirconia, or other ceramic, less than 25 microns thick, e.g., 5-10 microns thick. The alumina layer(s) may be applied at relatively low temperature. Once applied, the layer provides excellent hermeticity, and prevents electrical leakage. Even though very thin, the alumina layer retains excellent insulating characteristics. In one embodiment, an alumina layer less than about 6 microns thick provides an insulative coating that exhibits less than 10 pA of leakage current over an area 75 mils by 25 mils while soaking in a saline solution at temperatures up to 80.degree. C. over a three month period.
摘要:
A continuous glucose monitoring system may include a hand-held monitor, a transmitter, an insulin pump, and an orthogonally redundant glucose sensor, which may comprise an optical glucose sensor and a non-optical glucose sensor. The former may be a fiber optical sensor, including a competitive glucose binding affinity assay with a glucose analog and a fluorophore-labeled glucose receptor, which is interrogated by an optical interrogating system, e.g., a stacked planar integrated optical system. The non-optical sensor may be an electrochemical sensor having a plurality of electrodes distributed along the length thereof. Proximal portions of the optical and electrochemical sensors may be housed inside the transmitter and operationally coupled with instrumentation for, e.g., receiving signals from the sensors, converting to respective glucose values, and communicating the glucose values. The sensors' distal portions may be inserted into a user's body via a single delivery needle and may be co-located inside the user's body.
摘要:
A blood glucose sensing system includes a sensor and a sensor electronics device. The sensor includes a plurality of electrodes. The sensor electronics device includes stabilization circuitry. The stabilization circuitry causes a first voltage to be applied to one of the electrodes for a first timeframe and causes a second voltage to be applied to one of the electrodes for a second timeframe. The stabilization circuitry repeats the application of the first voltage and the second voltage to continue the anodic-cathodic cycle. The sensor electronics device may include a power supply, a regulator, and a voltage application device, where the voltage application device receives a regulated voltage from the regulator, applies a first voltage to an electrode for the first timeframe, and applies a second voltage to an electrode for the second timeframe.
摘要:
A thin film sensor, such as a glucose sensor, is provided for transcutaneous placement at a selected site within the body of a patient. The sensor includes several sensor layers that include conductive layers and includes a proximal segment defining conductive contacts adapted for electrical connection to a suitable monitor, and a distal segment with sensor electrodes for transcutaneous placement. The sensor electrode layers are disposed generally above each other, for example with the reference electrode above the working electrode and the working electrode above the counter electrode. The electrode layers are separated by dielectric layer.
摘要:
Embodiments of the invention provide analyte sensors having elements designed to modulate their chemical reactions as well as methods for making and using such sensors. In certain embodiments of the invention, the sensor includes a hydrophilic comb-copolymer having a central chain and a plurality of side chains coupled to the central chain, wherein at least one side chain comprises a silicone moiety.
摘要:
Embodiments of the invention provide analyte sensors having optimized permselective membranes and methods for making and using such sensors. Embodiments of the invention also provide analyte sensors such as those having porous matrices coated with an analyte sensing composition and methods for making and using such sensors. Illustrative embodiments include electrochemical glucose sensors having glucose oxidase coatings.
摘要:
A system and method for calibrating a sensor of a characteristic monitoring system in real time utilizes a self-calibration module for periodic determination of, and compensation for, the IR drop across unwanted resistances in a cell. A current-interrupt switch is used to open the self-calibration module circuit and either measure the IR drop using a high-frequency (MHz) ADC module, or estimate it through linear regression of acquired samples of the voltage across the sensor's working and reference electrodes (Vmeasured) over time. The IR drop is then subtracted from the closed-circuit value of Vmeasured to calculate the overpotential that exists in the cell (Vimportant). Vimportant may be further optimized by subtracting the value of the open-circuit voltage (Voc) across the sensor's working and reference electrodes. The values of Vmeasured and Vimportant are then controlled by respective first and second control units to compensate for the IR drop.
摘要:
Disclosed are a system and method for determining a metric and/or indicator of a reliability of a blood glucose sensor in providing glucose measurements. In one aspect, the metric and/or indicator may be computed based, at least in part, on an observed trend associated with signals generated by the blood glucose sensor.