Determination of stable isotopes of calcium in biological fluids by fast atom bombardment mass spectrometry.
Determination of stable isotopes of calcium in biological fluids by fast atom bombardment mass spectrometry.
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快原子轰击质谱法测定生物体液中钙的稳定同位素。
DOI：
10.1021/ac00264a042
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发表时间：
1983
影响因子：
7.4
通讯作者：
Smith,DL
中科院分区：
文献类型：
--
作者：
Smith,DL
用高分辨快原子轰击质谱法测定血浆和尿中钙的同位素丰度。由于该方法非常灵敏（> 5 X 1010隆恩/pg钙），因此仅需要2至5 μ l样品。血浆和尿液中 * 2Ca/* Ca比值的重复测量需要约3分钟，通常具有0.2- 0.5%的相对标准偏差。不需要样品制备，测量使用的是大型研究实验室中常见的仪器。多达20种不同的金属对哺乳动物的生命、生长和繁殖起着必要的作用。通过使用原子吸收、中子活化分析和X射线荧光光谱法，已经获得了关于正常和患病个体组织中必需和非必需元素水平的大量信息。此外，放射性同位素还被用作示踪剂，以阐明金属被人体吸收、分布、储存和排泄的过程。然而，我们对这些过程的理解尤其缺乏，因为道德约束严重限制了放射性同位素的使用。一般来说，儿童和育龄成人只有在非常特殊的情况下才能摄入放射性同位素。虽然大多数必需金属的稳定同位素都是高度浓缩的，但它们仅在少数情况下被用作生物研究的示踪剂。这主要是因为还没有一种令人满意的方法来分析生物体液中的稳定同位素。
Hlgh-resolutlon fast atom bombardment mass spectrometry was used to measure the Isotopic abundances of calcium In plasma and urine. Since the method Is very sensitive (> 5 X 1010 lons/pg of calcium), only 2 to 5 µ of sample Is required. Repetitive measurements of the* 2Ca/* Ca ratio In plasma and urine require about 3 min and typically have a relative standard deviation of 0.2-0.5%. No samplepreparation Is necessary and measurements are made by using Instrumen-tation that Is often available In larger research laboratories.As many as 20 different metals perform functions necessary for life, growth, and reproduction in mammals. Substantial information about the levels of both essential and nonessential elements in tissues of normal and diseased individuals has been obtained through use of atomic absorption, neutron activation analysis, and X-ray fluorescence spectrometry. In addition, radioisotopeshave been used as tracers to elucidate processes by which metals are absorbed, distributed, stored, and excretedby the body. Our understanding of these pro-cesses is, however, particularly deficient inhumans because ethical constraints severely restrict the use of radioisotopes. In general, radioisotopes may be ingested by children and child-bearing adults only in very special cases. Although stable isotopes of most of the essential metals are available highly enriched, they have been used as tracers for biological studies in only a few instances. This is primarily because a satisfactory method of analysis of stable isotopes in biological fluids has not been available.