Glucose implantable electrode

Updike SJ, Shults M, Ekman B. Implanting the glucose enzyme electrode problems, progress, and alternative solutions. Diabetes Care 1982, 5, 207-212. 

Ahmed S, Dack C, Farace G, Rigby G, Vadgama P. Tissue implanted glucose needle electrodes early sensor stabilisation and achievement of tissue-blood correlation during the run in period. Analytica Chimica Acta 2005, 537, 153-161. 

A glucose sensor system consisting of an oxygen electrode and a glucose oxidase electrode was recently implanted into the vena cava of a dog (McKean and Gough, 1988). The sensors operated in the potentio-static mode and were connected to an implantable telemetry system. Both the enzyme stability and the power consumption allowed operation of the system for three months. 

Serum contains electrooxidizable ascorbate, urate, and acetaminophen. These may contribute to the measured current, and thereby prevent one-point calibration of the implanted electrodes. To reduce the rate of the electrooxidation of these compounds, their flux to the wired enzyme layer is reduced by a special micromembrane [11]. The same membrane also reduces, to a lesser extent, the flux of glucose, thereby extending, at least to 30 mM, the linear part of the curve representing the dependence of the electrooxidation current on glucose concentration [11]. The required micromembranes of 5 x 10 cm area are synthesized in situ on the wired GOX layers by sequentially adsorbing polyanions and polycations. The micromembrane allows the simultaneous adjustment of the linear... 

The concepts of an artificial heart can be looked at in terms of a fuel cell driving an electric motor-driven pump (32), This was a program supported by the NIH in the 1970 s. The concept (Fig. 7) was that the heart could be run on a fuel cell consisting of one glucose-based electrode for oxidative power, the other electrode being used for the reduction of oxygen. A fuel cell was implanted in a dog, and ran for... 

Schmidtke DW, HcUct A (1998) Accuracy of the one-point in vivo calibration of Wired glucose oxidase electrodes implanted in jugular veins of rats in periods of rapid rise and decline of the glucose concentration. Anal Chem 70(10) 2149-2155... 

Most of the recent attention has been given to the development of subcutaneously implantable needle-type electrodes [14, 15, 34, 38], Such devices track blood glucose levels by measuring the glucose concentration in the interstitial fluid of the subcutaneous tissue (assuming the ratio of the blood/tissue levels is constant). Subcutaneously implantable devices are commonly designed to operate for a few days and be replaced by the patient. Success in this direction has reached the level of short-term human implantation ... 

E. Csoregi, D.W. Schmidtke, and A. Heller, Design and optimzation of a selective subcutaneously implantable gluocse electrode based on wired glucose oxidase. Anal. Chem. 67, 1240-1244 (1995). 

In the previous papers(12,13), we reported on the vessel access type, i.e. tubular type, glucose sensor. It consisted of a glucose electrode system with a GOX enzyme immobilized Nylon membrane and a glucose semipermeable membrane, and a reference oxygen electrode system. The sensor could directly measure up to 700 mg/dl of BGL in an arterial blood stream when it was placed into an external A-V shunt. This sensor, however, has some problems such as thrombus during in vivo testing without heparin and clinical complexity associated with implanting the sensor in a blood stream. 

Csoregi E, Quinn CP, Schmidtke DW, Lindquist SE, Pishko MV, Ye L, Katakis I, Hubbell JA, Heller A. Design, characterization, and one-point in vivo calibration of a subcutaneously implanted glucose electrode. Analytical Chemistry 1994,66, 3131-3138. 

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