Exchange of (18)O in the reaction of peroxynitrite with CO(2).
Exchange of (18)O in the reaction of peroxynitrite with CO(2).
复制标题
过氧亚硝酸盐与 CO(2) 反应中 (18)O 的交换。
DOI：
10.1016/j.freeradbiomed.2004.09.028
复制
发表时间：
2005
期刊：
影响因子：
--
通讯作者：
Silverman,DavidN
中科院分区：
文献类型：
--
作者：
Tu,Chingkuang;Quint,Patrick;Silverman,DavidN
我们使用膜入口质谱法和HPLC负电喷雾电离质谱法观察到CO 2 与过氧亚硝酸盐的反应中18 O的交换。当将过氧亚硝酸盐添加到含有与碳酸氢盐平衡的18 O-标记的CO 2 的溶液中时，发生交换。观察到从CO 2 暂时提高的18 O消耗速率，该速率大于由CO 2 的水合/脱水循环引起的18 O消耗速率。此外，我们检测到产物 NO3- 中出现了归因于 18 O 的质量峰。作为 18 O 交换的进一步测量，存在 18 O 的重新分布，使得双标记与单标记 CO2 的比率无法通过二项式展开来描述。这不是由于 CO2 的水合/脱水循环，而是很可能是由于 CO2 在与过氧亚硝酸盐的反应中循环利用。这种与CO 2 和过氧亚硝酸盐反应相关的18 O交换可能为研究这一重要过程开辟新的方法。
We have observed an exchange of18O in the reactions of CO2with peroxynitrite using membrane-inlet mass spectrometry and HPLC negative electrospray ionization mass spectrometry. The exchange appeared on addition of peroxynitrite to a solution containing18O-labeled CO2in equilibrium with bicarbonate. It was observed as a temporarily enhanced rate of depletion of18O from CO2, a rate that was greater than the rate of18O depletion caused by the hydration/dehydration cycle of CO2. In addition, we detected the appearance of mass peaks attributed to18O in product NO3–.As a further measure of the18O exchange, there was a redistribution of18O such that the ratio of doubly to singly labeled CO2could not be described by the binomial expansion. This is not due to the hydration/dehydration cycle of CO2but most likely to recycling of CO2in the reaction with peroxynitrite. This18O exchange associated with the reactions of CO2and peroxynitrite may open a new methodology for studying this significant process.