General method for determining ethylene oxide and related N7-guanine DNA adducts by gas chromatography-electron capture mass spectrometry.
General method for determining ethylene oxide and related N7-guanine DNA adducts by gas chromatography-electron capture mass spectrometry.
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气相色谱-电子捕获质谱测定环氧乙烷和相关 N7-鸟嘌呤 DNA 加合物的通用方法。
DOI：
10.1016/0021-9673(95)00545-x
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
Giese,RW
中科院分区：
文献类型：
--
作者：
Saha,M;Abushamaa,A;Giese,RW
向112 μg DNA样品中加标103 pg N7-（2′-羟乙基）鸟嘌呤和100 pg N7-（2′-羟乙基-d4）鸟嘌呤（内标物）。对样品进行以下顺序的步骤：在100°C下加热，用HCl沉淀DNA，与亚硝酸反应以形成相应的黄嘌呤，与五氟苄基溴反应两次（首先衍生NH，然后衍生OH），在二氧化硅上固相萃取并通过气相色谱-电子捕获质谱法检测。分析物和内标物的最终产物的绝对总产率为9.7%。方便地，三个化学反应在同一小瓶中顺序进行，并且除了洗涤步骤之外，仅通过蒸发分离。相应的N7-鸟嘌呤甲基，苯基和氧化苯乙烯加合物检测到约50 ng的水平，通过该程序，以表明该方法的通用性。
A 112-μg sample of DNA was spiked with 103 pg of N7-(2′-hydroxyethyl)guanine and 100 pg of N7-(2′-hydroxyethyl-d4)guanine, the internal standard. The sample was subjected to the following sequence of steps: heating at 100°C, precipitation of the DNA with HCl, reaction with nitrous acid to form the corresponding xanthines, reaction twice with pentafluorobenzyl bromide (first to derivatize NH, then OH), solid-phase extraction on silica and detection by gas chromatography-electron capture mass spectrometry. The absolute, overall yield of final product for both the analyte and internal standard was 9.7%. Conveniently, the three chemical reactions are conducted sequentially in the same vial and, aside from a washing step, are separated only by evaporations. Corresponding N7-guanine methyl, phenyl and styrene oxide adducts were detected at about the 50-ng level by the procedure, to indicate the generality of the method.