ARSENITE STIMULATED OXYGEN RADICAL ON NITRIC OXIDE RELEASE FROM ENDOTHELIAL CELL

碳基顺磁材料是EPR常用的材料 血氧测定，特别是在体内，但这些材料的EPR谱 通常显示一个以上的顺磁中心和/或相对较低 信号强度。来确定碳基的成分是否 物质可以被分离并在活性成分中浓缩，我们 使用密度梯度离心法将材料分离成 几个分数。我们研究了两种煤，Gloxy和Gloxy Pocahontas，发现这些材料具有很大的密度 分发。分离的密度分数具有非常不同的EPR 光谱和强度。煤原料中的活性成分 显示更均匀的EPR信号，并显著增加 EPR信号强度。在用印度墨水进行的类似研究中，只有轻微的 在分离材料的尝试中观察到了变化。这些 煤的研究结果可能会对更好的发展非常有用 EPR血氧测定仪探头。

Carbon based paramagnetic materials are frequently used for EPR oximetry, especially in vivo, but the EPR spectra of these materials often show more than one paramagnetic center and/or relatively low signal intensity. To determine whether the components of carbon based materials could be separated and enriched in the active component, we used density gradient centrifugation to separate the materials into several fractions. We studied two types of coals, gloxy and Pocahontas, and found these materials to have large density distribution. The separated density fractions had very different EPR spectra and intensities. The active component from the coal material displays a more homogeneous EPR signal, and significantly increased EPR signal intensity. In similar studies with India ink, only slight changes were observed in attempts to separate the material. These results with coals may be very useful in the development of better probes for EPR oximetry.