使用离子交换膜过滤器提取血清和尿液中的钙，用于热电离质谱法进行同位素富集测定。

Extraction of serum and urine calcium with ion exchange membrane filters for isotope enrichment determination using thermal ionization mass spectrometry.

作者信息

Vieira N E, Yergey A L

机构信息

Laboratory of Theoretical and Physical Biology, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA.

出版信息

Anal Chem. 1995 Nov 15;67(22):4217-9. doi: 10.1021/ac00118a028.

DOI:10.1021/ac00118a028

PMID:8633769

Abstract

The extraction of calcium from water, serum, and urine using Bio-Rex 25 mm ion exchange membrane filters was compared with the oxalate precipitation procedure currently used in our laboratory. Total recoveries of a known quantity of calcium loaded onto the membrane filters for water, serum and urine were as follows: (a) cation exchange filter, 85%, 74%, and 66%; (b) Chelex, 65%, 98%, and 20%; and (c) oxalate precipitation, 93%, 100%, and 96%, respectively. Regression analysis for precipitation versus ion exchange isotope ratio measurements of standards prepared using highly enriched calcium-44 showed slopes of unity. An improvement of automated sample analysis was observed for water and urine calcium samples extracted with ion exchange filters.

摘要

使用Bio-Rex 25 mm离子交换膜过滤器从水、血清和尿液中提取钙，并与我们实验室目前使用的草酸盐沉淀法进行了比较。加载到水、血清和尿液膜过滤器上的已知量钙的总回收率如下：(a)阳离子交换过滤器，分别为85%、74%和66%；(b)螯合树脂，分别为65%、98%和20%；(c)草酸盐沉淀法，分别为93%、100%和96%。对使用高度富集的钙-44制备的标准品进行沉淀与离子交换同位素比率测量的回归分析，斜率为1。在用离子交换过滤器提取的水和尿液钙样品中，观察到自动样品分析有所改进。