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.
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.
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DOI：
10.1021/ac970932u
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发表时间：
1998-04
影响因子：
7.4
通讯作者：
D. Schmidtke;A. Heller
中科院分区：
文献类型：
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作者：
D. Schmidtke;A. Heller
对静脉内植入的血糖传感器在静脉血糖浓度快速上升和下降期间进行一点体内校准的可行性假设进行了检验。将响应时间为10~90%、不耗氧的微型葡萄糖电极(5×10~(-4)cm~(-4)cm~2)植入肝素化大鼠颈静脉内，进行4h的实验，期间对血糖进行电流计监测。葡萄糖电极是通过电子传导氧化还原水凝胶将葡萄糖氧化酶的反应中心电连接到金电极表面而制成的。组成电极敏感层的氧化还原聚合物和酶通过交联被固定，因此电极没有扩散且容易被浸出的氧化还原介体。植入后1小时，这些电极可以准确地跟踪血糖浓度，当血糖浓度稳定时，当血糖浓度快速上升时，当血糖浓度急剧下降时，通过一点校准进行体内校准。对于假设的2分钟滞后时间，传感器读数与真实血糖浓度有很好的相关性，线性回归分析得出斜率为0.97+/-0.07，截距(偏差)为0.3+/-0.3 mm。相关系数R2为0.949+/-0.020，在2-22 mm范围内的百分比差值为1.9+/-1.0%。结果表明，结合了解和模拟皮下和血糖浓度之间的瞬时生理差异，即使在葡萄糖浓度迅速变化的情况下，也可以通过皮下植入的一点校准传感器进行校准。
The hypothesis of the feasibility of one-point in vivo calibration of intravenously implanted glucose sensors during periods of rapid rise and decline of venous blood glucose concentration was tested. Miniature (5 x 10(-4) cm2 mass transporting area) glucose electrodes with 10-90% response times < 2 min, that did not consume oxygen, were implanted in jugular veins of systemically heparinized rats and used in 4-h experiments, during which the blood glucose concentration was amperometrically monitored. The glucose electrodes were made by electrically connecting ("wiring") reaction centers of glucose oxidase through an electron-conducting redox hydrogel to gold electrode surfaces. The redox polymer and enzyme constituting the electrode sensing layer were immobilized by cross-linking, and thus the electrodes had no diffusional and readily leached redox mediator. One hour after their implantation, the electrodes accurately tracked the blood glucose concentration when calibrated in vivo by a one-point calibration, when the glucose concentration was steady, when rising rapidly, and when declining steeply. For an assumed 2-min lag time, the sensor readings were well correlated with the true blood glucose concentrations, with linear regression analysis yielding a slope of 0.97 +/- 0.07 and an intercept (bias) of 0.3 +/- 0.3 mM. The correlation coefficient, r2, was 0.949 +/- 0.020, and the percent difference through the 2-22 mM range was 1.9 +/- 1.0%. The results suggest that, in combination with understanding and modeling of transient physiological differences between the subcutaneous and the blood glucose concentrations, it will be possible to calibrate by one-point in vivo calibration subcutaneously implanted sensors, even while the glucose concentration changes rapidly.