Katz S A, Roth A C, Feigl E O
J Appl Physiol (1985). 1985 Nov;59(5):1660-4. doi: 10.1152/jappl.1985.59.5.1660.
An electrode and cuvette system has been developed for the continuous and rapid measurement of either blood CO2 tension or pH. The CO2 electrode consists of a 1.5-mm-diameter flat-tip glass pH electrode covered by a film of carbonic anhydrase solution, over which a 25-micron-thick dimethyl silicone membrane is attached. Porous ceramic filled with 20% polyacrylamide, equilibrated with a salt solution, serves as a salt bridge between a Ag-AgCl reference electrode and the pH electrode surface. The electrode is housed in a four-port cuvette assembly. Blood from a vessel of interest is delivered to the cuvette by means of an occlusive roller pump. The cuvette maintains the electrode and blood at a constant temperature and directs a continuous jet of blood against the electrode surface. The cuvette also allows for easy and frequent calibration of the electrode with either gas or liquid standards. The 90% response time of the CO2 electrode is 3.0 s for liquids and 1.3 s for gases. Removal of the dimethyl silicone membrane and carbonic anhydrase film yields a pH electrode that can continuously measure blood pH with a 90% response time of 1.6 s.
已开发出一种电极和比色皿系统，用于连续快速测量血液二氧化碳分压或pH值。二氧化碳电极由一个直径为1.5毫米的平头玻璃pH电极组成，该电极覆盖有一层碳酸酐酶溶液膜，在其上附着有一层25微米厚的二甲基硅氧烷膜。填充有20%聚丙烯酰胺并与盐溶液平衡的多孔陶瓷用作银-氯化银参比电极与pH电极表面之间的盐桥。该电极安装在一个四端口比色皿组件中。来自感兴趣血管的血液通过闭塞式滚轴泵输送到比色皿中。比色皿将电极和血液保持在恒定温度，并引导一股连续的血液射流冲击电极表面。比色皿还允许使用气体或液体标准品轻松且频繁地校准电极。二氧化碳电极对液体的90%响应时间为3.0秒，对气体为1.3秒。去除二甲基硅氧烷膜和碳酸酐酶膜后可得到一个pH电极，该电极可连续测量血液pH值，90%响应时间为1.6秒。
