Automated kinetic method for D-3-hydroxybutyrate in plasma or serum.
Automated kinetic method for D-3-hydroxybutyrate in plasma or serum.
复制标题
血浆或血清中 D-3-羟基丁酸的自动动力学方法。
作者：
C. McMurray;W. J. Blanchflower;D. Rice
本文基于动力学初速技术，对血浆或血清中3-羟基丁酸的测定进行了初速和线性优化：PH8.5，羟丁酸脱氢酶62.5U/L，NAD+浓度20 mmol/L。用Gilford 103和日立705分立分析仪进行测定，结果令人满意，结果与分段流动法相当。批内精密度(CV)从7.8%到0.6%不等，这取决于所使用的分析仪和3-羟基丁酸酯的浓度。分析回收率也依赖于3-羟基丁酸酯的浓度，在2 mmol/L时为99%，在9.5 mmol/L时为91%。加入草酸盐可消除乳酸脱氢酶/乳酸的干扰。在3-羟基丁酸酯的平衡分析方法中常用的联氨在这种分析中没有产生显著的优势，因此被省略了。用于检测的混合试剂在4摄氏度下至少稳定一周。分析这种代谢物的优势现在可以实现，这样就可以在人类和动物中识别临床和亚临床酮病。
This assay for 3-hydroxybutyrate in plasma or serum, based on kinetic initial-rate techniques, has been optimized with respect to initial rate and linearity as follows: pH 8.5, hydroxybutyrate dehydrogenase 62.5 U/L, and NAD+ concentration 20 mmol/L. We have used the assay satisfactorily with both the Gilford 103 and Hitachi 705 discrete analyzers, obtaining results that compare well with those by a segmented-flow method. Within-assay precision (CV) varied from 7.8 to 0.6%, depending on both the analyzer used and on the concentration of 3-hydroxybutyrate. Analytical recovery was also dependent on 3-hydroxybutyrate concentration, varying from 99% at 2 mmol/L to 91% at 9.5 mmol/L. Lactate dehydrogenase/lactate interference in this direct assay is eliminated by incorporating oxalate in the assay reagents. Hydrazine, commonly used in equilibrium methods of analysis for 3-hydroxybutyrate, produced no significant advantage in this assay and was omitted. The mixed reagents for the assay are stable at 4 degrees C for at least a week. The advantages of analysis for this metabolite may now be realized, so that clinical and subclinical ketosis can be identified in humans and animals.