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

Application of conducting polymers to biosensors.

Mathematical Handbook for Scientists and Engineers

The development of a robust method for integrating high-performance semiconductors on flexible plastics could enable exciting avenues in fundamental research and novel applications. One area of vital relevance is chemical and biological sensing, which if implemented on biocompatible substrates, could yield breakthroughs in implantable or wearable monitoring systems. Semiconducting nanowires (and nanotubes) are particularly sensitive chemical sensors because of their high surface-to-volume ratios. Here, we present a scalable and parallel process for transferring hundreds of pre-aligned silicon nanowires onto plastic to yield highly ordered films for low-power sensor chips. The nanowires are excellent field-effect transistors, and, as sensors, exhibit parts-per-billion sensitivity to NO2, a hazardous pollutant. We also use SiO2 surface chemistries to construct a ‘nano-electronic nose’ library, which can distinguish acetone and hexane vapours via distributed responses. The excellent sensing performance coupled with bendable plastic could open up opportunities in portable, wearable or even implantable sensors.

Highly ordered nanowire arrays on plastic substrates for ultrasensitive flexible chemical sensors

A small diameter flexible electrode designed for subcutaneous in vivo amperometric monitoring of glucose is described. The electrode is designed to allow “one-point” in vivo calibration, i.e., to have zero output current at zero glucose concentration, even in the presence of other electroreactive species of serum or blood. The electrode is preferably three or four-layered, with the layers serially deposited within a recess upon the tip of a polyamide insulated gold wire. A first glucose concentration-to-current transducing layer is overcoated with an electrically insulating and glucose flux limiting layer (second layer) on which, optionally, an immobilized interference-eliminating horseradish peroxidase based film is deposited (third layer). An outer (fourth) layer is biocompatible.

Subcutaneous glucose electrode

Miniaturized thin-film biosensors using covalently immobilized glucose oxidase☆

Miniaturized multi-enzyme biosensors integrated with pH sensors on flexible polymer carriers for in vivo applications

Micromachined flow sensors based on thin film germanium thermistors offer high flow sensitivities and short response times. Using the controlled overtemperature scheme, the measurable air flow velocity ranges from ±0.01 to ±200 m/s and the response time to large step changes of the air velocity is less than 20 ms. In the constant power mode, a signal rise time of 1.6 ms has been demonstrated by the application of shock waves. An air flow measuring range from 0.6 ml/h to at least 150 l/h has been achieved, e.g. with a rectangular flow channel of 0.54 mm 2 cross-sectional area. Using a lookup table transformation, a linearized output signal can be obtained within 25 μs.

Wide range semiconductor flow sensors

In this paper, we present an integrated Coulter counter that applies a liquid aperture. The Coulter aperture is defined by a non-coaxial sheath of a conductive sample liquid that is surrounded on three sides by a non-conductive sheath liquid. The main advantage of this approach is that it prevents channel blocking, since the channel’s physical dimensions can be much larger than the Coulter aperture. Furthermore, the dimensions of the aperture can be dynamically adapted to the size of the particle by changing the flow-rates of the sample liquid and the sheath liquid. Both the sample and the sheath liquid are aqueous to prevent unstable flow conditions due to surface tension effects at the interface of the sheath liquid and the sample liquid. Diffusion of ions from the sample liquid into the sheath liquid is limited as long as a minimum flow-rate of 0.5 μl/s is used. The maximum flow-rate is determined by the occurrence of instable flow behaviour at flow-rates higher than 10 μl/s. The device can be made in a simple process requiring only four lithographic steps. Measurement results show that a high sensitivity can be obtained in a channel with relatively large physical dimensions.

http://biodevices.et.tudelft.nl/Bio-projects/ShapeVision/pdf2.pdf

Franz Kohl

Papers

Miniaturized thin-film biosensors using covalently immobilized glucose oxidase☆

Miniaturized multi-enzyme biosensors integrated with pH sensors on flexible polymer carriers for in vivo applications

Wide range semiconductor flow sensors

Integrated Coulter counter based on 2-dimensional liquid aperture control

Development of miniaturized semiconductor flow sensors