复方枸橼酸钠注射液,内含枸橼酸、枸橼酸钠和葡萄糖,是用于间接输血时的血液保养液。注射液中枸橼酸钠含量测定,各快速检验资料都采用酸量法。该法以橙黄Ⅳ为指示剂,因滴定突跃不明显,致使终点难以判断,不能得到准确的结果。其它方法如非水溶液滴定法、离子交换法都因繁琐费时,不便采用。作者试应用离子选择性电极法来测定其枸橼酸钠含量。结果尚满意。离子选择性电极法是借助于敏感膜对某一离子有选择性响应而产生电位,该电位随待测离子的活度不同而变化,理论符合Nernst方程。但是存在电极响应值往往因电极活化状态不同而不同和电极电位漂移等缺点,为此,本文采用样品溶液和被测成分的标准溶液同时交替测定而拟定出的对比法,使上述缺点得到克服,结果较为准确。在测量仪器方面,即采用 Compound sodium citrate injection, containing citric acid, sodium citrate and glucose, is used for blood transfusion at the time of blood maintenance solution. Injection sodium citrate determination, the rapid test data are used acid method. The method of orange Ⅳ as an indicator, because titration jump is not obvious, resulting in difficult to determine the endpoint, can not get accurate results. Other methods such as non-aqueous titration, ion exchange method are complicated and time-consuming, inconvenience to adopt. The authors try to use ion selective electrode method to determine the sodium citrate content. The result is still satisfactory. Ion selective electrode method is by means of a sensitive membrane selective response to a certain ion potential, the potential varies with the measured activity of different ions, the theory with the Nernst equation. However, there are some disadvantages such as different electrode response values ​​due to different activated states of the electrodes and electrode potential drift. Therefore, in this paper, the above-mentioned shortcoming is overcome by using the comparative method of simultaneous determination of the standard solution of the sample solution and the tested component, The result is more accurate. In measuring instruments, that is used