酶法和离子选择电极法测定血清钾、钠的比较

目的: 比较酶法与离子选择电极法(ion-selective electrodes,ISE)测定血清钾、钠的优缺点。方法: 以定值血清为标样,用酶法及ISE分别测定高、低值钾和钠;同时随机取临床标本50份作对比实验,并作统计学分析。结果: 精密度显示酶法天内K+、Na+的CV<1.98%,天间K+、Na+的CV<2.26%;线性范围满足于临床;对K+和Na+测定结果两种方法均呈正相关关系(P<0.01);污染率酶法为0.66%-1.15%,ISE为1.15%-2.32%。结论: 酶法与ISE可交替检测血清K+、Na+,方便临床,但酶法检测具有简便、精确、快速、重复性及相关性好等特点,用血量少,适用于全自动生化分析仪。

Comparison of enzymic method and ion-selective electrode method in detection of serum potassium and sodium

Objective:To compare enzymic method and ion-selective electrodes(ISE) in detection of serum potassium(K+) and sodium(Na+).Methods:Fixed-value serum as the control samples,fifty clinical samples were collected at random and levels of K+ and Na+ in these samples were tested by the two methods.Results:CV of serum levels of K+ and Na+ by enzymic method was less than 1.98% in the same day and less than 2.26% in different days.The linearity was satisfied with the clinical requirement.There was a positive correlation between the two methods in measurement of serum levels of K+ and Na+.The contamination rate of enzymic method was 0.66% to 1.15% and that of the ISE was 1.15% to 2.32%.Conclusions:The enzymic method and the ISE can be used alternately,and the enzymic method is more convenient,precise and there are good repetitiveness and correlation.Moreover,the enzymic method to test the level of K+ and Na+ in serum could be used in automatic biochemical analysator because of less consumption of serum.