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

The present invention relates generally to systems and methods for measuring an analyte in a host. More particularly, the present invention relates to systems and methods for transcutaneous measurement of glucose in a host.

Transcutaneous analyte sensor

Systems and methods for applying time-dependent algorithmic compensation functions to data output from a continuous analyte sensor. Some embodiments determine a time since sensor implantation and/or whether a newly initialized sensor has been used previously.

Systems and methods for processing analyte sensor data

Two types of photomodulation of orientations of liquid crystals (LCs) are reviewed: 1) order–disorder phase transitions of LCs induced by photochemical reactions of photochromic molecules and 2) order–order alignment change of LCs (change in LC directors) induced by photochemical reactions or without photochemical events. Both processes produce a large refractive-index modulation, which forms the basis of a range of photonic applications. Various modes of photomodulation of orientations of LCs with plausible mechanisms and their possible applications in photonics are described.

Photomodulation of liquid crystal orientations for photonic applications

Systems and methods for integrating a continuous glucose sensor, including a receiver, a medicament delivery device, and optionally a single point glucose monitor are provided. Manual integrations provide for a physical association between the devices wherein a user (for example, patient or doctor) manually selects the amount, type, and/or time of delivery. Semi-automated integration of the devices includes integrations wherein an operable connection between the integrated components aids the user (for example, patient or doctor) in selecting, inputting, calculating, or validating the amount, type, or time of medicament delivery of glucose values, for example, by transmitting data to another component and thereby reducing the amount of user input required. Automated integration between the devices includes integrations wherein an operable connection between the integrated components provides for full control of the system without required user interaction.

Integrated delivery device for continuous glucose sensor

Significant loss of activity of thick-film gold electrodes is observed when they are used for continuous amperometric detection of H2O2 in 0.1 M sodium phosphate buffer and in serum samples. Triple-step potential waveforms are utilized for pulsed amperometric detection to clean the surface of conventional electrodes from poisoning substances and reactivate them, thus maintaining uniform electrode activity. This technique is applied to a microprocessor-controlled multichannel sensor system with poly(vinylacetate)-based enzyme membranes, which are attached to the thick-film gold electrodes by adhesion. The parameters of a triple-step potential sequence, which are dependent on the electrochemical behaviour of the membrane-coated thick-film gold electrodes, have been determined so that efficient cleaning of the electrode surfaces is obtained and at the same time the characteristics of the enzyme sensors are not influenced. The potential sequence consists of an oxidation potential of 800 mV, a reduction potential of 100 mV and the detection potential of 600 mV (versus Ag/AgCl) for hydrogen peroxide. The triple-step potential waveform is applied to the multichannel system for simultaneous determdination of glucose and sucrose in buffered aqueous solutions and for detection of glucose in serum samples. A sensor response with improved sensitivity and reproducibility is obtained. With the on-line cleaning of the electrode surfaces by application of the triple-step potential waveform, uniform electrode activity is maintained even when the glucose sensors are operated in serum samples. The sensor response, obtained with continuous amperometric detection, proves to be limited by adsorption processes of H2O2 at the surface of the thick-film gold electrodes. On the other hand, the sensor response obtained with application of the triple-step potential waveform indicates limitation by diffusion processes and the upper limit of the linear range is extended from 5 to 12 mM for glucose and from 4 to 15 mM for sucrose in aqueous solutions.

A triple-step potential waveform at enzyme multisensors with thick-film gold electrodes for detection of glucose and sucrose

Determination of the first hyperpolarizability of four octupolar molecules and their dipolar subunits via hyper-Rayleigh scattering in solution

Photosensitive cholesteric polysiloxanes, which contain an azo dye, were irradiated with linearly polarized light. The cholesteric samples were oriented in the Grandjean texture. Before irradiation they reflected circularly polarized light in the near infrared region. For perpendicular incidence, only one order of reflection was observed. Upon irradiation with linearly polarized light, which is absorbed by the azo dye, additional reflection bands appeared in the visible part of the spectrum. It turned out that the additional reflection is caused by a new Bragg type grating which shows higher reflection orders. The formation of the grating is based on the periodic deformation of the helical ordering of the molecules. The deformation is periodic, as due to photoselection, only dye molecules in equidistant layers with a suitable orientation absorb radiation. For low exposure, the grating reflects linearly polarized light. After continued irradiation, the reflection bands disappear almost completely....

Cholesteric liquid crystalline siloxanes with azo dye. Generation of additional reflection bands with linearly polarized light

Poly(vinyl acetate)-based membrane materials for thick-film liquid sensors are presented. They can be used for the formation of potentiometric membranes as well as for the immobilization of enzymes. They show excellent adhesion to thick-film electrodes and can be laminated to form multilayer membranes. All are suitable for mechanical application to transducers either by screen printing or by solder dispenser systems. Examples of four channel amperometric and potentiometric multisensors are presented and the composition of the membrane mixtures is discussed.

Design and application of thick-film multisensors

Symmetric cyanine dyes of the kind Me2N+CH(CHCH)nNMe2 normally exhibit no first hyperpolarizabilities β but have relatively long absorption wavelengths. Therefore they are not suitable NLO chromophores for second-order applications. However, if these chromophores are converted into octupolar molecules either by coupling an extra aldiminium group onto the dye molecule or by grafting three vinamidinium units onto a benzene ring, NLO chromophores with considerable first hyperpolarizabilities are obtained. To prove this, the β values of both kinds of octupoles have been determined via hyper-Rayleigh scattering in solution at 1064 nm.

Ch. Bräuchle

Papers

A triple-step potential waveform at enzyme multisensors with thick-film gold electrodes for detection of glucose and sucrose

Determination of the first hyperpolarizability of four octupolar molecules and their dipolar subunits via hyper-Rayleigh scattering in solution

Cholesteric liquid crystalline siloxanes with azo dye. Generation of additional reflection bands with linearly polarized light

Design and application of thick-film multisensors

Determination of the First Hyperpolarizabilities of Octupolar Molecular Ions Made from Symmetric Cyanine Dyes