Vaidya R, Wilkins E
Department of Chemical Engineering, University of New Mexico, Albuquerque 87131.
Med Eng Phys. 1994 Sep;16(5):416-21. doi: 10.1016/1350-4533(90)90008-v.
The prerequisite for the continuous in vivo monitoring of glucose concentration is the development of an implantable glucose sensor with long-term stability. A new enzyme electrode concept featuring fluid-state glucose oxidase modified carbon powder along with a cross-linked glucose oxidase enzyme layer has been developed. The glucose sensor incorporating this enzyme electrode has been tested in vitro at 37 degrees C. It has a lifetime of three months after which it can be recharged with fresh enzyme. The next step in the characterization of this sensor is its in vitro behaviour in the presence of interfering substances commonly encountered in human blood. Here we report such a study of the sensor. The glucose diffusion membranes used were polycarbonate membranes. We used standard polycarbonate membranes (membranes treated with polyvinylpyrrolidone or PVP), PVP-free polycarbonate membranes, and standard polycarbonate membranes coated with positively and negatively charged hydrogel layers. The sensors showed a response to glucose concentrations < 300 mg dL-1, both in pure phosphate buffer and in the presence of interferences. The influence of ascorbic acid, bilirubin, creatinine, L-cystine, glycine, uric acid and urea on the amperometric signal of the sensor was investigated. The polycarbonate membrane coated with the negatively charged hydrogel layer provided good protection for the enzyme electrode, especially in the presence of ascorbic acid and uric acid.
对葡萄糖浓度进行持续的体内监测的前提是开发出具有长期稳定性的可植入式葡萄糖传感器。一种新的酶电极概念已经被开发出来，其特点是采用液态葡萄糖氧化酶修饰的碳粉以及交联的葡萄糖氧化酶酶层。包含这种酶电极的葡萄糖传感器已在37摄氏度下进行了体外测试。它的使用寿命为三个月，之后可以用新鲜酶进行充电。该传感器特性表征的下一步是研究其在人体血液中常见干扰物质存在下的体外行为。在此我们报告对该传感器的此类研究。所使用的葡萄糖扩散膜是聚碳酸酯膜。我们使用了标准聚碳酸酯膜（用聚乙烯吡咯烷酮或PVP处理过的膜）、无PVP的聚碳酸酯膜以及涂覆有带正电和负电水凝胶层的标准聚碳酸酯膜。这些传感器在纯磷酸盐缓冲液以及存在干扰物质的情况下，对葡萄糖浓度<300 mg dL-1均有响应。研究了抗坏血酸、胆红素、肌酐、L-胱氨酸、甘氨酸、尿酸和尿素对传感器安培信号的影响。涂覆有带负电水凝胶层的聚碳酸酯膜为酶电极提供了良好的保护，尤其是在抗坏血酸和尿酸存在的情况下。
