The Interaction of Water with Solid Surfaces: Fundamental Aspects Revisited

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

Recent advances in catalysis have made the incorporation of fluorine into complex organic molecules easier than ever before, but selective, general and practical fluorination reactions remain sought after. Fluorination of molecules often imparts desirable properties, such as metabolic and thermal stability, and fluorinated molecules are therefore frequently used as pharmaceuticals or materials. But the formation of carbon-fluorine bonds in complex molecules is a significant challenge. Here we discuss reactions to make organofluorides that have emerged within the past few years and which exemplify how to overcome some of the intricate challenges associated with fluorination.

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Catalysis for fluorination and trifluoromethylation

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

The electrochemical activity of Au electrodes held at constant potential for anodic detection of carbohydrates in alkaline media eventually decays to zero. This loss of response is a consequence of the accumulation of adsorbed oxidation products on the electrode surface. Although it is well-known that these "poisons" can be removed by oxidative desorption simultaneously with formation of surface oxide, we have discovered that electrodes fouled during the detection of glucose yield a cathodic peak at -0.77 V vs SCE resulting from reductive desorption of these species. Incorporation of the reductive desorption process into wave forms for pulsed electrochemical detection (PED) permits a significant decrease in the time periods traditionally allowed for the oxidative and reductive reactivation of the electrode with a resulting increase in wave form frequency. A 6.7-Hz wave form using E(red) = -1.00 V (t(red) = 10 ms), E(oxd) = +0.60 V (t(oxd) = 10 ms), and E(det) = +0.10 V (t(del) = 50 ms, t(int) = 50 ms) is applied for detection of glucose in a LC-PED system and is demonstrated to yield a sub-picomole detection limit with a linear dynamic range extending over three decades.

Fast wave forms for pulsed electrochemical detection of glucose by incorporation of reductive desorption of oxidation products.

Scanning electrochemical microscopy (SECM) has been used to study electron transfer at Al and Al alloy surfaces, employing the mediators hydroquinone, hydroquinone sulfonate, anthraquinone-2,6-disulfonate, and anthraquinone-2-sulfonate. Both oxidation and reduction processes are examined. SECM, in combination with scanning electron microscopy/energy-dispersive X-ray analysis, reveals that Cu-containing secondary phase particles exhibit the highest electron transfer activity for both oxidation and reduction reactions on the AA 2024-T3 surface. Although electron transfer is fastest at the intermetallic particles, it also occurs on the alloy matrix under acidic conditions. The charge carried by the mediator appears to have little influence on the electron transfer process despite the fact that the matrix oxide surface is positively charged below pH 7.

Studies of Electron Transfer at Aluminum Alloy Surfaces by Scanning Electrochemical Microscopy

The adsorption of water on Ni(110) has been studied by thermal desorption spectroscopy (TDS), work function (ΔΦ), Fourier transform infrared reflection–absorption spectroscopy (FTIR‐RAS), low energy electron diffraction (LEED), and electron‐stimulated desorption ion angular distribution (ESDIAD). The major findings of this study are the following: (1) Water molecules in the chemisorbed c(2×2) half‐monolayer do not cluster and the plane of the molecules is highly inclined to the surface normal; (2) no ESDIAD evidence of oriented water dimers is observed at 130 K and no FTIR activity is observed following adsorption at 80 K until multilayers are populated; (3) water has been measured to partially dissociate at a minimum temperature of 205±2 K; (4)the binding energy of water to the Ni(110) surface is increased by H‐bonding to adsorbed hydroxyls (produced by the partial dissociation) in a linear OH(ad)/H2O complex with planar symmetry in the [001] direction. This bonding results in a higher temperature desorp...

Mark B. Jensen

Papers

Fast wave forms for pulsed electrochemical detection of glucose by incorporation of reductive desorption of oxidation products.

Studies of Electron Transfer at Aluminum Alloy Surfaces by Scanning Electrochemical Microscopy

Structural phenomena related to associative and dissociative adsorption of water on Ni(110)

Self-healing ability and particle size effect of encapsulated cerium nitrate into pH sensitive microcapsules

Application of SECM to Corrosion Studies